这篇文章主要介绍“PostgreSQL中执行插入函数的实现逻辑是什么",在日常操作中，相信很多人在一种数据库系统中执行插入函数的实现逻辑是什么问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答“PostgreSQL中执行插入函数的实现逻辑是什么"的疑惑有所帮助！接下来，请跟着小编一起来学习吧！
一、基础信息
按惯例，首先看看执行插入函数使用的数据结构、宏定义以及依赖的函数等数据结构/宏定义1，可修改状态
/* -
*PlanStatenode
*
* wenevereal instant ianyplanstatenodes；这只是一个普遍现象
*抽象超类用于所有计划状态类型的节点.
* -
*/
typedefstructPlanState
{
NodeTagtype
计划*计划；/*associatedPlannode*/
EState * state/*执行时间，个人状态
* nodestopinttooneestateforhewhole
*顶层计划*/
execprocnodemtdecprocnode/* functiontorentnexttuple */
execprocnodemtdecprocnode real/*实际函数ifaboveisa
nbsp; * wrapper */
Instrumentation *instrument; /* Optional runtime stats for this node */
WorkerInstrumentation *worker_instrument; /* per-worker instrumentation */
/*
* Common structural data for all Plan types. These links to subsidiary
* state trees parallel links in the associated plan tree (except for the
* subPlan list, which does not exist in the plan tree).
*/
ExprState *qual; /* boolean qual condition */
struct PlanState *lefttree; /* input plan tree(s) */
struct PlanState *righttree;
List *initPlan; /* Init SubPlanState nodes (un-correlated expr
* subselects) */
List *subPlan; /* SubPlanState nodes in my expressions */
/*
* State for management of parameter-change-driven rescanning
*/
Bitmapset *chgParam; /* set of IDs of changed Params */
/*
* Other run-time state needed by most if not all node types.
*/
TupleTableSlot *ps_ResultTupleSlot; /* slot for my result tuples */
ExprContext *ps_ExprContext; /* node's expression-evaluation context */
ProjectionInfo *ps_ProjInfo; /* info for doing tuple projection */
/*
* Scanslot's descriptor if known. This is a bit of a hack, but otherwise
* it's hard for expression compilation to optimize based on the
* descriptor, without encoding knowledge about all executor nodes.
*/
TupleDesc scandesc;
} PlanState;
/* ----------------
* ModifyTableState information
* ----------------
*/
typedef struct ModifyTableState
{
PlanState ps; /* its first field is NodeTag */
CmdType operation; /* INSERT, UPDATE, or DELETE */
bool canSetTag; /* do we set the command tag/es_processed? */
bool mt_done; /* are we done? */
PlanState **mt_plans; /* subplans (one per target rel) */
int mt_nplans; /* number of plans in the array */
int mt_whichplan; /* which one is being executed (0..n-1) */
ResultRelInfo *resultRelInfo; /* per-subplan target relations */
ResultRelInfo *rootResultRelInfo; /* root target relation (partitioned
* table root) */
List **mt_arowmarks; /* per-subplan ExecAuxRowMark lists */
EPQState mt_epqstate; /* for evaluating EvalPlanQual rechecks */
bool fireBSTriggers; /* do we need to fire stmt triggers? */
TupleTableSlot *mt_existing; /* slot to store existing target tuple in */
List *mt_excludedtlist; /* the excluded pseudo relation's tlist */
TupleTableSlot *mt_conflproj; /* CONFLICT ... SET ... projection target */
/* Tuple-routing support info */
struct PartitionTupleRouting *mt_partition_tuple_routing;
/* controls transition table population for specified operation */
struct TransitionCaptureState *mt_transition_capture;
/* controls transition table population for INSERT...ON CONFLICT UPDATE */
struct TransitionCaptureState *mt_oc_transition_capture;
/* Per plan map for tuple conversion from child to root */
TupleConversionMap **mt_per_subplan_tupconv_maps;
} ModifyTableState;
2、TupleTableSlot
/*----------
* The executor stores tuples in a "tuple table" which is a List of
* independent TupleTableSlots. There are several cases we need to handle:
* 1. physical tuple in a disk buffer page
* 2. physical tuple constructed in palloc'ed memory
* 3. "minimal" physical tuple constructed in palloc'ed memory
* 4. "virtual" tuple consisting of Datum/isnull arrays
*
* The first two cases are similar in that they both deal with "materialized"
* tuples, but resource management is different. For a tuple in a disk page
* we need to hold a pin on the buffer until the TupleTableSlot's reference
* to the tuple is dropped; while for a palloc'd tuple we usually want the
* tuple pfree'd when the TupleTableSlot's reference is dropped.
*
* A "minimal" tuple is handled similarly to a palloc'd regular tuple.
* At present, minimal tuples never are stored in buffers, so there is no
* parallel to case 1. Note that a minimal tuple has no "system columns".
* (Actually, it could have an OID, but we have no need to access the OID.)
*
* A "virtual" tuple is an optimization used to minimize physical data
* copying in a nest of plan nodes. Any pass-by-reference Datums in the
* tuple point to storage that is not directly associated with the
* TupleTableSlot; generally they will point to part of a tuple stored in
* a lower plan node's output TupleTableSlot, or to a function result
* constructed in a plan node's per-tuple econtext. It is the responsibility
* of the generating plan node to be sure these resources are not released
* for as long as the virtual tuple needs to be valid. We only use virtual
* tuples in the result slots of plan nodes --- tuples to be copied anywhere
* else need to be "materialized" into physical tuples. Note also that a
* virtual tuple does not have any "system columns".
*
* It is also possible for a TupleTableSlot to hold both physical and minimal
* copies of a tuple. This is done when the slot is requested to provide
* the format other than the one it currently holds. (Originally we attempted
* to handle such requests by replacing one format with the other, but that
* had the fatal defect of invalidating any pass-by-reference Datums pointing
* into the existing slot contents.) Both copies must contain identical data
* payloads when this is the case.
*
* The Datum/isnull arrays of a TupleTableSlot serve double duty. When the
* slot contains a virtual tuple, they are the authoritative data. When the
* slot contains a physical tuple, the arrays contain data extracted from
* the tuple. (In this state, any pass-by-reference Datums point into
* the physical tuple.) The extracted information is built "lazily",
* ie, only as needed. This serves to avoid repeated extraction of data
* from the physical tuple.
*
* A TupleTableSlot can also be "empty", holding no valid data. This is
* the only valid state for a freshly-created slot that has not yet had a
* tuple descriptor assigned to it. In this state, tts_isempty must be
* true, tts_shouldFree false, tts_tuple NULL, tts_buffer InvalidBuffer,
* and tts_nvalid zero.
*
* The tupleDescriptor is simply referenced, not copied, by the TupleTableSlot
* code. The caller of ExecSetSlotDescriptor() is responsible for providing
* a descriptor that will live as long as the slot does. (Typically, both
* slots and descriptors are in per-query memory and are freed by memory
* context deallocation at query end; so it's not worth providing any extra
* mechanism to do more. However, the slot will increment the tupdesc
* reference count if a reference-counted tupdesc is supplied.)
*
* When tts_shouldFree is true, the physical tuple is "owned" by the slot
* and should be freed when the slot's reference to the tuple is dropped.
*
* If tts_buffer is not InvalidBuffer, then the slot is holding a pin
* on the indicated buffer page; drop the pin when we release the
* slot's reference to that buffer. (tts_shouldFree should always be
* false in such a case, since presumably tts_tuple is pointing at the
* buffer page.)
*
* tts_nvalid indicates the number of valid columns in the tts_values/isnull
* arrays. When the slot is holding a "virtual" tuple this must be equal
* to the descriptor's natts. When the slot is holding a physical tuple
* this is equal to the number of columns we have extracted (we always
* extract columns from left to right, so there are no holes).
*
* tts_values/tts_isnull are allocated when a descriptor is assigned to the
* slot; they are of length equal to the descriptor's natts.
*
* tts_mintuple must always be NULL if the slot does not hold a "minimal"
* tuple. When it does, tts_mintuple points to the actual MinimalTupleData
* object (the thing to be pfree'd if tts_shouldFreeMin is true). If the slot
* has only a minimal and not also a regular physical tuple, then tts_tuple
* points at tts_minhdr and the fields of that struct are set correctly
* for access to the minimal tuple; in particular, tts_minhdr.t_data points
* MINIMAL_TUPLE_OFFSET bytes before tts_mintuple. This allows column
* extraction to treat the case identically to regular physical tuples.
*
* tts_slow/tts_off are saved state for slot_deform_tuple, and should not
* be touched by any other code.
*----------
*/
typedef struct TupleTableSlot
{
NodeTag type;
bool tts_isempty; /* true = slot is empty */
bool tts_shouldFree; /* should pfree tts_tuple? */
bool tts_shouldFreeMin; /* should pfree tts_mintuple? */
#define FIELDNO_TUPLETABLESLOT_SLOW 4
bool tts_slow; /* saved state for slot_deform_tuple */
#define FIELDNO_TUPLETABLESLOT_TUPLE 5
HeapTuple tts_tuple; /* physical tuple, or NULL if virtual */
#define FIELDNO_TUPLETABLESLOT_TUPLEDESCRIPTOR 6
TupleDesc tts_tupleDescriptor; /* slot's tuple descriptor */
MemoryContext tts_mcxt; /* slot itself is in this context */
Buffer tts_buffer; /* tuple's buffer, or InvalidBuffer */
#define FIELDNO_TUPLETABLESLOT_NVALID 9
int tts_nvalid; /* # of valid values in tts_values */
#define FIELDNO_TUPLETABLESLOT_VALUES 10
Datum *tts_values; /* current per-attribute values */
#define FIELDNO_TUPLETABLESLOT_ISNULL 11
bool *tts_isnull; /* current per-attribute isnull flags */
MinimalTuple tts_mintuple; /* minimal tuple, or NULL if none */
HeapTupleData tts_minhdr; /* workspace for minimal-tuple-only case */
#define FIELDNO_TUPLETABLESLOT_OFF 14
uint32 tts_off; /* saved state for slot_deform_tuple */
bool tts_fixedTupleDescriptor; /* descriptor can't be changed */
} TupleTableSlot;
3、EState
/* ----------------
* EState information
*
* Master working state for an Executor invocation
* ----------------
*/
typedef struct EState
{
NodeTag type;
/* Basic state for all query types: */
ScanDirection es_direction; /* current scan direction */
Snapshot es_snapshot; /* time qual to use */
Snapshot es_crosscheck_snapshot; /* crosscheck time qual for RI */
List *es_range_table; /* List of RangeTblEntry */
PlannedStmt *es_plannedstmt; /* link to top of plan tree */
const char *es_sourceText; /* Source text from QueryDesc */
JunkFilter *es_junkFilter; /* top-level junk filter, if any */
/* If query can insert/delete tuples, the command ID to mark them with */
CommandId es_output_cid;
/* Info about target table(s) for insert/update/delete queries: */
ResultRelInfo *es_result_relations; /* array of ResultRelInfos */
int es_num_result_relations; /* length of array */
ResultRelInfo *es_result_relation_info; /* currently active array elt */
/*
* Info about the target partitioned target table root(s) for
* update/delete queries. They required only to fire any per-statement
* triggers defined on the table. It exists separately from
* es_result_relations, because partitioned tables don't appear in the
* plan tree for the update/delete cases.
*/
ResultRelInfo *es_root_result_relations; /* array of ResultRelInfos */
int es_num_root_result_relations; /* length of the array */
/*
* The following list contains ResultRelInfos created by the tuple routing
* code for partitions that don't already have one.
*/
List *es_tuple_routing_result_relations;
/* Stuff used for firing triggers: */
List *es_trig_target_relations; /* trigger-only ResultRelInfos */
TupleTableSlot *es_trig_tuple_slot; /* for trigger output tuples */
TupleTableSlot *es_trig_oldtup_slot; /* for TriggerEnabled */
TupleTableSlot *es_trig_newtup_slot; /* for TriggerEnabled */
/* Parameter info: */
ParamListInfo es_param_list_info; /* values of external params */
ParamExecData *es_param_exec_vals; /* values of internal params */
QueryEnvironment *es_queryEnv; /* query environment */
/* Other working state: */
MemoryContext es_query_cxt; /* per-query context in which EState lives */
List *es_tupleTable; /* List of TupleTableSlots */
List *es_rowMarks; /* List of ExecRowMarks */
uint64 es_processed; /* # of tuples processed */
Oid es_lastoid; /* last oid processed (by INSERT) */
int es_top_eflags; /* eflags passed to ExecutorStart */
int es_instrument; /* OR of InstrumentOption flags */
bool es_finished; /* true when ExecutorFinish is done */
List *es_exprcontexts; /* List of ExprContexts within EState */
List *es_subplanstates; /* List of PlanState for SubPlans */
List *es_auxmodifytables; /* List of secondary ModifyTableStates */
/*
* this ExprContext is for per-output-tuple operations, such as constraint
* checks and index-value computations. It will be reset for each output
* tuple. Note that it will be created only if needed.
*/
ExprContext *es_per_tuple_exprcontext;
/*
* These fields are for re-evaluating plan quals when an updated tuple is
* substituted in READ COMMITTED mode. es_epqTuple[] contains tuples that
* scan plan nodes should return instead of whatever they'd normally
* return, or NULL if nothing to return; es_epqTupleSet[] is true if a
* particular array entry is valid; and es_epqScanDone[] is state to
* remember if the tuple has been returned already. Arrays are of size
* list_length(es_range_table) and are indexed by scan node scanrelid - 1.
*/
HeapTuple *es_epqTuple; /* array of EPQ substitute tuples */
bool *es_epqTupleSet; /* true if EPQ tuple is provided */
bool *es_epqScanDone; /* true if EPQ tuple has been fetched */
bool es_use_parallel_mode; /* can we use parallel workers? */
/* The per-query shared memory area to use for parallel execution. */
struct dsa_area *es_query_dsa;
/*
* JIT information. es_jit_flags indicates whether JIT should be performed
* and with which options. es_jit is created on-demand when JITing is
* performed.
*/
int es_jit_flags;
struct JitContext *es_jit;
} EState;
4、ResultRelInfo
/*
* ResultRelInfo
*
* Whenever we update an existing relation, we have to update indexes on the
* relation, and perhaps also fire triggers. ResultRelInfo holds all the
* information needed about a result relation, including indexes.
*/
typedef struct ResultRelInfo
{
NodeTag type;
/* result relation's range table index */
Index ri_RangeTableIndex;
/* relation descriptor for result relation */
Relation ri_RelationDesc;
/* # of indices existing on result relation */
int ri_NumIndices;
/* array of relation descriptors for indices */
RelationPtr ri_IndexRelationDescs;
/* array of key/attr info for indices */
IndexInfo **ri_IndexRelationInfo;
/* triggers to be fired, if any */
TriggerDesc *ri_TrigDesc;
/* cached lookup info for trigger functions */
FmgrInfo *ri_TrigFunctions;
/* array of trigger WHEN expr states */
ExprState **ri_TrigWhenExprs;
/* optional runtime measurements for triggers */
Instrumentation *ri_TrigInstrument;
/* FDW callback functions, if foreign table */
struct FdwRoutine *ri_FdwRoutine;
/* available to save private state of FDW */
void *ri_FdwState;
/* true when modifying foreign table directly */
bool ri_usesFdwDirectModify;
/* list of WithCheckOption's to be checked */
List *ri_WithCheckOptions;
/* list of WithCheckOption expr states */
List *ri_WithCheckOptionExprs;
/* array of constraint-checking expr states */
ExprState **ri_ConstraintExprs;
/* for removing junk attributes from tuples */
JunkFilter *ri_junkFilter;
/* list of RETURNING expressions */
List *ri_returningList;
/* for computing a RETURNING list */
ProjectionInfo *ri_projectReturning;
/* list of arbiter indexes to use to check conflicts */
List *ri_onConflictArbiterIndexes;
/* ON CONFLICT evaluation state */
OnConflictSetState *ri_onConflict;
/* partition check expression */
List *ri_PartitionCheck;
/* partition check expression state */
ExprState *ri_PartitionCheckExpr;
/* relation descriptor for root partitioned table */
Relation ri_PartitionRoot;
/* true if ready for tuple routing */
bool ri_PartitionReadyForRouting;
} ResultRelInfo;
5、List
typedef struct ListCell ListCell;
typedef struct List
{
NodeTag type; /* T_List, T_IntList, or T_OidList */
int length;
ListCell *head;
ListCell *tail;
} List;
struct ListCell
{
union
{
void *ptr_value;
int int_value;
Oid oid_value;
} data;
ListCell *next;
};
6、TransitionCaptureState
typedef struct TransitionCaptureState
{
/*
* Is there at least one trigger specifying each transition relation on
* the relation explicitly named in the DML statement or COPY command?
* Note: in current usage, these flags could be part of the private state,
* but it seems possibly useful to let callers see them.
*/
bool tcs_delete_old_table;
bool tcs_update_old_table;
bool tcs_update_new_table;
bool tcs_insert_new_table;
/*
* For UPDATE and DELETE, AfterTriggerSaveEvent may need to convert the
* new and old tuples from a child table's format to the format of the
* relation named in a query so that it is compatible with the transition
* tuplestores. The caller must store the conversion map here if so.
*/
TupleConversionMap *tcs_map;
/*
* For INSERT and COPY, it would be wasteful to convert tuples from child
* format to parent format after they have already been converted in the
* opposite direction during routing. In that case we bypass conversion
* and allow the inserting code (copy.c and nodeModifyTable.c) to provide
* the original tuple directly.
*/
HeapTuple tcs_original_insert_tuple;
/*
* Private data including the tuplestore(s) into which to insert tuples.
*/
struct AfterTriggersTableData *tcs_private;
} TransitionCaptureState;
*7、ModifyTable *
/* ----------------
* ModifyTable node -
* Apply rows produced by subplan(s) to result table(s),
* by inserting, updating, or deleting.
*
* Note that rowMarks and epqParam are presumed to be valid for all the
* subplan(s); they can't contain any info that varies across subplans.
* ----------------
*/
typedef struct ModifyTable
{
Plan plan;
CmdType operation; /* INSERT, UPDATE, or DELETE */
bool canSetTag; /* do we set the command tag/es_processed? */
Index nominalRelation; /* Parent RT index for use of EXPLAIN */
/* RT indexes of non-leaf tables in a partition tree */
List *partitioned_rels;
bool partColsUpdated; /* some part key in hierarchy updated */
List *resultRelations; /* integer list of RT indexes */
int resultRelIndex; /* index of first resultRel in plan's list */
int rootResultRelIndex; /* index of the partitioned table root */
List *plans; /* plan(s) producing source data */
List *withCheckOptionLists; /* per-target-table WCO lists */
List *returningLists; /* per-target-table RETURNING tlists */
List *fdwPrivLists; /* per-target-table FDW private data lists */
Bitmapset *fdwDirectModifyPlans; /* indices of FDW DM plans */
List *rowMarks; /* PlanRowMarks (non-locking only) */
int epqParam; /* ID of Param for EvalPlanQual re-eval */
OnConflictAction onConflictAction; /* ON CONFLICT action */
List *arbiterIndexes; /* List of ON CONFLICT arbiter index OIDs */
List *onConflictSet; /* SET for INSERT ON CONFLICT DO UPDATE */
Node *onConflictWhere; /* WHERE for ON CONFLICT UPDATE */
Index exclRelRTI; /* RTI of the EXCLUDED pseudo relation */
List *exclRelTlist; /* tlist of the EXCLUDED pseudo relation */
} ModifyTable;
8、OnConflictAction
/*
* OnConflictAction -
* "ON CONFLICT" clause type of query
*
* This is needed in both parsenodes.h and plannodes.h, so put it here...
*/
typedef enum OnConflictAction
{
ONCONFLICT_NONE, /* No "ON CONFLICT" clause */
ONCONFLICT_NOTHING, /* ON CONFLICT ... DO NOTHING */
ONCONFLICT_UPDATE /* ON CONFLICT ... DO UPDATE */
} OnConflictAction;
8、MemoryContext
typedef struct MemoryContextData
{
NodeTag type; /* identifies exact kind of context */
/* these two fields are placed here to minimize alignment wastage: */
bool isReset; /* T = no space alloced since last reset */
bool allowInCritSection; /* allow palloc in critical section */
const MemoryContextMethods *methods; /* virtual function table */
MemoryContext parent; /* NULL if no parent (toplevel context) */
MemoryContext firstchild; /* head of linked list of children */
MemoryContext prevchild; /* previous child of same parent */
MemoryContext nextchild; /* next child of same parent */
const char *name; /* context name (just for debugging) */
const char *ident; /* context ID if any (just for debugging) */
MemoryContextCallback *reset_cbs; /* list of reset/delete callbacks */
} MemoryContextData;
/* utils/palloc.h contains typedef struct MemoryContextData *MemoryContext */
/*
* Type MemoryContextData is declared in nodes/memnodes.h. Most users
* of memory allocation should just treat it as an abstract type, so we
* do not provide the struct contents here.
*/
typedef struct MemoryContextData *MemoryContext;
依赖的函数
1、ExecMaterializeSlot
/* --------------------------------
* ExecMaterializeSlot
* Force a slot into the "materialized" state.
*
* This causes the slot's tuple to be a local copy not dependent on
* any external storage. A pointer to the contained tuple is returned.
*
* A typical use for this operation is to prepare a computed tuple
* for being stored on disk. The original data may or may not be
* virtual, but in any case we need a private copy for heap_insert
* to scribble on.
* --------------------------------
*/
HeapTuple
ExecMaterializeSlot(TupleTableSlot *slot)
{
MemoryContext oldContext;
/*
* sanity checks
*/
Assert(slot != NULL);
Assert(!slot->tts_isempty);
/*
* If we have a regular physical tuple, and it's locally palloc'd, we have
* nothing to do.
*/
if (slot->tts_tuple && slot->tts_shouldFree)
return slot->tts_tuple;
/*
* Otherwise, copy or build a physical tuple, and store it into the slot.
*
* We may be called in a context that is shorter-lived than the tuple
* slot, but we have to ensure that the materialized tuple will survive
* anyway.
*/
oldContext = MemoryContextSwitchTo(slot->tts_mcxt);//内存上下文切换至slot->tts_mcxt
slot->tts_tuple = ExecCopySlotTuple(slot);
slot->tts_shouldFree = true;
MemoryContextSwitchTo(oldContext);//内存上下文切换回原来
/*
* Drop the pin on the referenced buffer, if there is one.
*/
if (BufferIsValid(slot->tts_buffer))
ReleaseBuffer(slot->tts_buffer);
slot->tts_buffer = InvalidBuffer;
/*
* Mark extracted state invalid. This is important because the slot is
* not supposed to depend any more on the previous external data; we
* mustn't leave any dangling pass-by-reference datums in tts_values.
* However, we have not actually invalidated any such datums, if there
* happen to be any previously fetched from the slot. (Note in particular
* that we have not pfree'd tts_mintuple, if there is one.)
*/
slot->tts_nvalid = 0;
/*
* On the same principle of not depending on previous remote storage,
* forget the mintuple if it's not local storage. (If it is local
* storage, we must not pfree it now, since callers might have already
* fetched datum pointers referencing it.)
*/
if (!slot->tts_shouldFreeMin)
slot->tts_mintuple = NULL;
return slot->tts_tuple;
}
#ifndef FRONTEND
static inline MemoryContext
MemoryContextSwitchTo(MemoryContext context)
{
MemoryContext old = CurrentMemoryContext;
CurrentMemoryContext = context;
return old;
}
#endif /* FRONTEND */
2、HeapTupleSetOid
#define HeapTupleSetOid(tuple, oid) \ HeapTupleHeaderSetOid((tuple)->t_data, (oid))
3、ExecBRInsertTriggers
TupleTableSlot *
ExecBRInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TupleTableSlot *slot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
HeapTuple slottuple = ExecMaterializeSlot(slot);
HeapTuple newtuple = slottuple;
HeapTuple oldtuple;
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_INSERT |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_BEFORE;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
LocTriggerData.tg_newtuplebuf = InvalidBuffer;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_BEFORE,
TRIGGER_TYPE_INSERT))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, newtuple))
continue;
LocTriggerData.tg_trigtuple = oldtuple = newtuple;
LocTriggerData.tg_trigtuplebuf = InvalidBuffer;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (oldtuple != newtuple && oldtuple != slottuple)
heap_freetuple(oldtuple);
if (newtuple == NULL)
return NULL; /* "do nothing" */
}
if (newtuple != slottuple)
{
/*
* Return the modified tuple using the es_trig_tuple_slot. We assume
* the tuple was allocated in per-tuple memory context, and therefore
* will go away by itself. The tuple table slot should not try to
* clear it.
*/
TupleTableSlot *newslot = estate->es_trig_tuple_slot;
TupleDesc tupdesc = RelationGetDescr(relinfo->ri_RelationDesc);
if (newslot->tts_tupleDescriptor != tupdesc)
ExecSetSlotDescriptor(newslot, tupdesc);
ExecStoreTuple(newtuple, newslot, InvalidBuffer, false);
slot = newslot;
}
return slot;
}
4、ExecIRInsertTriggers
TupleTableSlot *
ExecIRInsertTriggers(EState *estate, ResultRelInfo *relinfo,
TupleTableSlot *slot)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
HeapTuple slottuple = ExecMaterializeSlot(slot);
HeapTuple newtuple = slottuple;
HeapTuple oldtuple;
TriggerData LocTriggerData;
int i;
LocTriggerData.type = T_TriggerData;
LocTriggerData.tg_event = TRIGGER_EVENT_INSERT |
TRIGGER_EVENT_ROW |
TRIGGER_EVENT_INSTEAD;
LocTriggerData.tg_relation = relinfo->ri_RelationDesc;
LocTriggerData.tg_newtuple = NULL;
LocTriggerData.tg_oldtable = NULL;
LocTriggerData.tg_newtable = NULL;
LocTriggerData.tg_newtuplebuf = InvalidBuffer;
for (i = 0; i < trigdesc->numtriggers; i++)
{
Trigger *trigger = &trigdesc->triggers[i];
if (!TRIGGER_TYPE_MATCHES(trigger->tgtype,
TRIGGER_TYPE_ROW,
TRIGGER_TYPE_INSTEAD,
TRIGGER_TYPE_INSERT))
continue;
if (!TriggerEnabled(estate, relinfo, trigger, LocTriggerData.tg_event,
NULL, NULL, newtuple))
continue;
LocTriggerData.tg_trigtuple = oldtuple = newtuple;
LocTriggerData.tg_trigtuplebuf = InvalidBuffer;
LocTriggerData.tg_trigger = trigger;
newtuple = ExecCallTriggerFunc(&LocTriggerData,
i,
relinfo->ri_TrigFunctions,
relinfo->ri_TrigInstrument,
GetPerTupleMemoryContext(estate));
if (oldtuple != newtuple && oldtuple != slottuple)
heap_freetuple(oldtuple);
if (newtuple == NULL)
return NULL; /* "do nothing" */
}
if (newtuple != slottuple)
{
/*
* Return the modified tuple using the es_trig_tuple_slot. We assume
* the tuple was allocated in per-tuple memory context, and therefore
* will go away by itself. The tuple table slot should not try to
* clear it.
*/
TupleTableSlot *newslot = estate->es_trig_tuple_slot;
TupleDesc tupdesc = RelationGetDescr(relinfo->ri_RelationDesc);
if (newslot->tts_tupleDescriptor != tupdesc)
ExecSetSlotDescriptor(newslot, tupdesc);
ExecStoreTuple(newtuple, newslot, InvalidBuffer, false);
slot = newslot;
}
return slot;
}
5、ExecForeignInsert
-- 函数指针 typedef TupleTableSlot *(*ExecForeignInsert_function) (EState *estate, ResultRelInfo *rinfo, TupleTableSlot *slot, TupleTableSlot *planSlot); ExecForeignInsert_function ExecForeignInsert;
6、RelationGetRelid
/* * RelationGetRelid * Returns the OID of the relation */ #define RelationGetRelid(relation) ((relation)->rd_id)
7、ExecWithCheckOptions
/*
* ExecWithCheckOptions -- check that tuple satisfies any WITH CHECK OPTIONs
* of the specified kind.
*
* Note that this needs to be called multiple times to ensure that all kinds of
* WITH CHECK OPTIONs are handled (both those from views which have the WITH
* CHECK OPTION set and from row level security policies). See ExecInsert()
* and ExecUpdate().
*/
void
ExecWithCheckOptions(WCOKind kind, ResultRelInfo *resultRelInfo,
TupleTableSlot *slot, EState *estate)
{
Relation rel = resultRelInfo->ri_RelationDesc;
TupleDesc tupdesc = RelationGetDescr(rel);
ExprContext *econtext;
ListCell *l1,
*l2;
/*
* We will use the EState's per-tuple context for evaluating constraint
* expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Check each of the constraints */
forboth(l1, resultRelInfo->ri_WithCheckOptions,
l2, resultRelInfo->ri_WithCheckOptionExprs)
{
WithCheckOption *wco = (WithCheckOption *) lfirst(l1);
ExprState *wcoExpr = (ExprState *) lfirst(l2);
/*
* Skip any WCOs which are not the kind we are looking for at this
* time.
*/
if (wco->kind != kind)
continue;
/*
* WITH CHECK OPTION checks are intended to ensure that the new tuple
* is visible (in the case of a view) or that it passes the
* 'with-check' policy (in the case of row security). If the qual
* evaluates to NULL or FALSE, then the new tuple won't be included in
* the view or doesn't pass the 'with-check' policy for the table.
*/
if (!ExecQual(wcoExpr, econtext))
{
char *val_desc;
Bitmapset *modifiedCols;
Bitmapset *insertedCols;
Bitmapset *updatedCols;
switch (wco->kind)
{
/*
* For WITH CHECK OPTIONs coming from views, we might be
* able to provide the details on the row, depending on
* the permissions on the relation (that is, if the user
* could view it directly anyway). For RLS violations, we
* don't include the data since we don't know if the user
* should be able to view the tuple as that depends on the
* USING policy.
*/
case WCO_VIEW_CHECK:
/* See the comment in ExecConstraints(). */
if (resultRelInfo->ri_PartitionRoot)
{
HeapTuple tuple = ExecFetchSlotTuple(slot);
TupleDesc old_tupdesc = RelationGetDescr(rel);
TupleConversionMap *map;
rel = resultRelInfo->ri_PartitionRoot;
tupdesc = RelationGetDescr(rel);
/* a reverse map */
map = convert_tuples_by_name(old_tupdesc, tupdesc,
gettext_noop("could not convert row type"));
if (map != NULL)
{
tuple = do_convert_tuple(tuple, map);
ExecSetSlotDescriptor(slot, tupdesc);
ExecStoreTuple(tuple, slot, InvalidBuffer, false);
}
}
insertedCols = GetInsertedColumns(resultRelInfo, estate);
updatedCols = GetUpdatedColumns(resultRelInfo, estate);
modifiedCols = bms_union(insertedCols, updatedCols);
val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
slot,
tupdesc,
modifiedCols,
64);
ereport(ERROR,
(errcode(ERRCODE_WITH_CHECK_OPTION_VIOLATION),
errmsg("new row violates check option for view \"%s\"",
wco->relname),
val_desc ? errdetail("Failing row contains %s.",
val_desc) : 0));
break;
case WCO_RLS_INSERT_CHECK:
case WCO_RLS_UPDATE_CHECK:
if (wco->polname != NULL)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("new row violates row-level security policy \"%s\" for table \"%s\"",
wco->polname, wco->relname)));
else
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("new row violates row-level security policy for table \"%s\"",
wco->relname)));
break;
case WCO_RLS_CONFLICT_CHECK:
if (wco->polname != NULL)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("new row violates row-level security policy \"%s\" (USING expression) for table \"%s\"",
wco->polname, wco->relname)));
else
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("new row violates row-level security policy (USING expression) for table \"%s\"",
wco->relname)));
break;
default:
elog(ERROR, "unrecognized WCO kind: %u", wco->kind);
break;
}
}
}
}
8、ExecConstraints
/*
* ExecConstraints - check constraints of the tuple in 'slot'
*
* This checks the traditional NOT NULL and check constraints.
*
* The partition constraint is *NOT* checked.
*
* Note: 'slot' contains the tuple to check the constraints of, which may
* have been converted from the original input tuple after tuple routing.
* 'resultRelInfo' is the final result relation, after tuple routing.
*/
void
ExecConstraints(ResultRelInfo *resultRelInfo,
TupleTableSlot *slot, EState *estate)
{
Relation rel = resultRelInfo->ri_RelationDesc;
TupleDesc tupdesc = RelationGetDescr(rel);
TupleConstr *constr = tupdesc->constr;
Bitmapset *modifiedCols;
Bitmapset *insertedCols;
Bitmapset *updatedCols;
Assert(constr || resultRelInfo->ri_PartitionCheck);
if (constr && constr->has_not_null)
{
int natts = tupdesc->natts;
int attrChk;
for (attrChk = 1; attrChk <= natts; attrChk++)
{
Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1);
if (att->attnotnull && slot_attisnull(slot, attrChk))
{
char *val_desc;
Relation orig_rel = rel;
TupleDesc orig_tupdesc = RelationGetDescr(rel);
/*
* If the tuple has been routed, it's been converted to the
* partition's rowtype, which might differ from the root
* table's. We must convert it back to the root table's
* rowtype so that val_desc shown error message matches the
* input tuple.
*/
if (resultRelInfo->ri_PartitionRoot)
{
HeapTuple tuple = ExecFetchSlotTuple(slot);
TupleConversionMap *map;
rel = resultRelInfo->ri_PartitionRoot;
tupdesc = RelationGetDescr(rel);
/* a reverse map */
map = convert_tuples_by_name(orig_tupdesc, tupdesc,
gettext_noop("could not convert row type"));
if (map != NULL)
{
tuple = do_convert_tuple(tuple, map);
ExecSetSlotDescriptor(slot, tupdesc);
ExecStoreTuple(tuple, slot, InvalidBuffer, false);
}
}
insertedCols = GetInsertedColumns(resultRelInfo, estate);
updatedCols = GetUpdatedColumns(resultRelInfo, estate);
modifiedCols = bms_union(insertedCols, updatedCols);
val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
slot,
tupdesc,
modifiedCols,
64);
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("null value in column \"%s\" violates not-null constraint",
NameStr(att->attname)),
val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
errtablecol(orig_rel, attrChk)));
}
}
}
if (constr && constr->num_check > 0)
{
const char *failed;
if ((failed = ExecRelCheck(resultRelInfo, slot, estate)) != NULL)
{
char *val_desc;
Relation orig_rel = rel;
/* See the comment above. */
if (resultRelInfo->ri_PartitionRoot)
{
HeapTuple tuple = ExecFetchSlotTuple(slot);
TupleDesc old_tupdesc = RelationGetDescr(rel);
TupleConversionMap *map;
rel = resultRelInfo->ri_PartitionRoot;
tupdesc = RelationGetDescr(rel);
/* a reverse map */
map = convert_tuples_by_name(old_tupdesc, tupdesc,
gettext_noop("could not convert row type"));
if (map != NULL)
{
tuple = do_convert_tuple(tuple, map);
ExecSetSlotDescriptor(slot, tupdesc);
ExecStoreTuple(tuple, slot, InvalidBuffer, false);
}
}
insertedCols = GetInsertedColumns(resultRelInfo, estate);
updatedCols = GetUpdatedColumns(resultRelInfo, estate);
modifiedCols = bms_union(insertedCols, updatedCols);
val_desc = ExecBuildSlotValueDescription(RelationGetRelid(rel),
slot,
tupdesc,
modifiedCols,
64);
ereport(ERROR,
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("new row for relation \"%s\" violates check constraint \"%s\"",
RelationGetRelationName(orig_rel), failed),
val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
errtableconstraint(orig_rel, failed)));
}
}
}
9、ExecPartitionCheck
/*
* ExecPartitionCheck --- check that tuple meets the partition constraint.
*
* Returns true if it meets the partition constraint. If the constraint
* fails and we're asked to emit to error, do so and don't return; otherwise
* return false.
*/
bool
ExecPartitionCheck(ResultRelInfo *resultRelInfo, TupleTableSlot *slot,
EState *estate, bool emitError)
{
ExprContext *econtext;
bool success;
/*
* If first time through, build expression state tree for the partition
* check expression. Keep it in the per-query memory context so they'll
* survive throughout the query.
*/
if (resultRelInfo->ri_PartitionCheckExpr == NULL)
{
List *qual = resultRelInfo->ri_PartitionCheck;
resultRelInfo->ri_PartitionCheckExpr = ExecPrepareCheck(qual, estate);
}
/*
* We will use the EState's per-tuple context for evaluating constraint
* expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/*
* As in case of the catalogued constraints, we treat a NULL result as
* success here, not a failure.
*/
success = ExecCheck(resultRelInfo->ri_PartitionCheckExpr, econtext);
/* if asked to emit error, don't actually return on failure */
if (!success && emitError)
ExecPartitionCheckEmitError(resultRelInfo, slot, estate);
return success;
}
10、ExecCheckIndexConstraints
/* ----------------------------------------------------------------
* ExecCheckIndexConstraints
*
* This routine checks if a tuple violates any unique or
* exclusion constraints. Returns true if there is no conflict.
* Otherwise returns false, and the TID of the conflicting
* tuple is returned in *conflictTid.
*
* If 'arbiterIndexes' is given, only those indexes are checked.
* NIL means all indexes.
*
* Note that this doesn't lock the values in any way, so it's
* possible that a conflicting tuple is inserted immediately
* after this returns. But this can be used for a pre-check
* before insertion.
* ----------------------------------------------------------------
*/
bool
ExecCheckIndexConstraints(TupleTableSlot *slot,
EState *estate, ItemPointer conflictTid,
List *arbiterIndexes)
{
ResultRelInfo *resultRelInfo;
int i;
int numIndices;
RelationPtr relationDescs;
Relation heapRelation;
IndexInfo **indexInfoArray;
ExprContext *econtext;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
ItemPointerData invalidItemPtr;
bool checkedIndex = false;
ItemPointerSetInvalid(conflictTid);
ItemPointerSetInvalid(&invalidItemPtr);
/*
* Get information from the result relation info structure.
*/
resultRelInfo = estate->es_result_relation_info;
numIndices = resultRelInfo->ri_NumIndices;
relationDescs = resultRelInfo->ri_IndexRelationDescs;
indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
heapRelation = resultRelInfo->ri_RelationDesc;
/*
* We will use the EState's per-tuple context for evaluating predicates
* and index expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/*
* For each index, form index tuple and check if it satisfies the
* constraint.
*/
for (i = 0; i < numIndices; i++)
{
Relation indexRelation = relationDescs[i];
IndexInfo *indexInfo;
bool satisfiesConstraint;
if (indexRelation == NULL)
continue;
indexInfo = indexInfoArray[i];
if (!indexInfo->ii_Unique && !indexInfo->ii_ExclusionOps)
continue;
/* If the index is marked as read-only, ignore it */
if (!indexInfo->ii_ReadyForInserts)
continue;
/* When specific arbiter indexes requested, only examine them */
if (arbiterIndexes != NIL &&
!list_member_oid(arbiterIndexes,
indexRelation->rd_index->indexrelid))
continue;
if (!indexRelation->rd_index->indimmediate)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("ON CONFLICT does not support deferrable unique constraints/exclusion constraints as arbiters"),
errtableconstraint(heapRelation,
RelationGetRelationName(indexRelation))));
checkedIndex = true;
/* Check for partial index */
if (indexInfo->ii_Predicate != NIL)
{
ExprState *predicate;
/*
* If predicate state not set up yet, create it (in the estate's
* per-query context)
*/
predicate = indexInfo->ii_PredicateState;
if (predicate == NULL)
{
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
indexInfo->ii_PredicateState = predicate;
}
/* Skip this index-update if the predicate isn't satisfied */
if (!ExecQual(predicate, econtext))
continue;
}
/*
* FormIndexDatum fills in its values and isnull parameters with the
* appropriate values for the column(s) of the index.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
satisfiesConstraint =
check_exclusion_or_unique_constraint(heapRelation, indexRelation,
indexInfo, &invalidItemPtr,
values, isnull, estate, false,
CEOUC_WAIT, true,
conflictTid);
if (!satisfiesConstraint)
return false;
}
if (arbiterIndexes != NIL && !checkedIndex)
elog(ERROR, "unexpected failure to find arbiter index");
return true;
}
11、ExecOnConflictUpdate
/*
* ExecOnConflictUpdate --- execute UPDATE of INSERT ON CONFLICT DO UPDATE
*
* Try to lock tuple for update as part of speculative insertion. If
* a qual originating from ON CONFLICT DO UPDATE is satisfied, update
* (but still lock row, even though it may not satisfy estate's
* snapshot).
*
* Returns true if we're done (with or without an update), or false if
* the caller must retry the INSERT from scratch.
*/
static bool
ExecOnConflictUpdate(ModifyTableState *mtstate,
ResultRelInfo *resultRelInfo,
ItemPointer conflictTid,
TupleTableSlot *planSlot,
TupleTableSlot *excludedSlot,
EState *estate,
bool canSetTag,
TupleTableSlot **returning)
{
ExprContext *econtext = mtstate->ps.ps_ExprContext;
Relation relation = resultRelInfo->ri_RelationDesc;
ExprState *onConflictSetWhere = resultRelInfo->ri_onConflict->oc_WhereClause;
HeapTupleData tuple;
HeapUpdateFailureData hufd;
LockTupleMode lockmode;
HTSU_Result test;
Buffer buffer;
/* Determine lock mode to use */
lockmode = ExecUpdateLockMode(estate, resultRelInfo);
/*
* Lock tuple for update. Don't follow updates when tuple cannot be
* locked without doing so. A row locking conflict here means our
* previous conclusion that the tuple is conclusively committed is not
* true anymore.
*/
tuple.t_self = *conflictTid;
test = heap_lock_tuple(relation, &tuple, estate->es_output_cid,
lockmode, LockWaitBlock, false, &buffer,
&hufd);
switch (test)
{
case HeapTupleMayBeUpdated:
/* success! */
break;
case HeapTupleInvisible:
/*
* This can occur when a just inserted tuple is updated again in
* the same command. E.g. because multiple rows with the same
* conflicting key values are inserted.
*
* This is somewhat similar to the ExecUpdate()
* HeapTupleSelfUpdated case. We do not want to proceed because
* it would lead to the same row being updated a second time in
* some unspecified order, and in contrast to plain UPDATEs
* there's no historical behavior to break.
*
* It is the user's responsibility to prevent this situation from
* occurring. These problems are why SQL-2003 similarly specifies
* that for SQL MERGE, an exception must be raised in the event of
* an attempt to update the same row twice.
*/
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(tuple.t_data)))
ereport(ERROR,
(errcode(ERRCODE_CARDINALITY_VIOLATION),
errmsg("ON CONFLICT DO UPDATE command cannot affect row a second time"),
errhint("Ensure that no rows proposed for insertion within the same command have duplicate constrained values.")));
/* This shouldn't happen */
elog(ERROR, "attempted to lock invisible tuple");
break;
case HeapTupleSelfUpdated:
/*
* This state should never be reached. As a dirty snapshot is used
* to find conflicting tuples, speculative insertion wouldn't have
* seen this row to conflict with.
*/
elog(ERROR, "unexpected self-updated tuple");
break;
case HeapTupleUpdated:
if (IsolationUsesXactSnapshot())
ereport(ERROR,
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
errmsg("could not serialize access due to concurrent update")));
/*
* As long as we don't support an UPDATE of INSERT ON CONFLICT for
* a partitioned table we shouldn't reach to a case where tuple to
* be lock is moved to another partition due to concurrent update
* of the partition key.
*/
Assert(!ItemPointerIndicatesMovedPartitions(&hufd.ctid));
/*
* Tell caller to try again from the very start.
*
* It does not make sense to use the usual EvalPlanQual() style
* loop here, as the new version of the row might not conflict
* anymore, or the conflicting tuple has actually been deleted.
*/
ReleaseBuffer(buffer);
return false;
default:
elog(ERROR, "unrecognized heap_lock_tuple status: %u", test);
}
/*
* Success, the tuple is locked.
*
* Reset per-tuple memory context to free any expression evaluation
* storage allocated in the previous cycle.
*/
ResetExprContext(econtext);
/*
* Verify that the tuple is visible to our MVCC snapshot if the current
* isolation level mandates that.
*
* It's not sufficient to rely on the check within ExecUpdate() as e.g.
* CONFLICT ... WHERE clause may prevent us from reaching that.
*
* This means we only ever continue when a new command in the current
* transaction could see the row, even though in READ COMMITTED mode the
* tuple will not be visible according to the current statement's
* snapshot. This is in line with the way UPDATE deals with newer tuple
* versions.
*/
ExecCheckHeapTupleVisible(estate, &tuple, buffer);
/* Store target's existing tuple in the state's dedicated slot */
ExecStoreTuple(&tuple, mtstate->mt_existing, buffer, false);
/*
* Make tuple and any needed join variables available to ExecQual and
* ExecProject. The EXCLUDED tuple is installed in ecxt_innertuple, while
* the target's existing tuple is installed in the scantuple. EXCLUDED
* has been made to reference INNER_VAR in setrefs.c, but there is no
* other redirection.
*/
econtext->ecxt_scantuple = mtstate->mt_existing;
econtext->ecxt_innertuple = excludedSlot;
econtext->ecxt_outertuple = NULL;
if (!ExecQual(onConflictSetWhere, econtext))
{
ReleaseBuffer(buffer);
InstrCountFiltered1(&mtstate->ps, 1);
return true; /* done with the tuple */
}
if (resultRelInfo->ri_WithCheckOptions != NIL)
{
/*
* Check target's existing tuple against UPDATE-applicable USING
* security barrier quals (if any), enforced here as RLS checks/WCOs.
*
* The rewriter creates UPDATE RLS checks/WCOs for UPDATE security
* quals, and stores them as WCOs of "kind" WCO_RLS_CONFLICT_CHECK,
* but that's almost the extent of its special handling for ON
* CONFLICT DO UPDATE.
*
* The rewriter will also have associated UPDATE applicable straight
* RLS checks/WCOs for the benefit of the ExecUpdate() call that
* follows. INSERTs and UPDATEs naturally have mutually exclusive WCO
* kinds, so there is no danger of spurious over-enforcement in the
* INSERT or UPDATE path.
*/
ExecWithCheckOptions(WCO_RLS_CONFLICT_CHECK, resultRelInfo,
mtstate->mt_existing,
mtstate->ps.state);
}
/* Project the new tuple version */
ExecProject(resultRelInfo->ri_onConflict->oc_ProjInfo);
/*
* Note that it is possible that the target tuple has been modified in
* this session, after the above heap_lock_tuple. We choose to not error
* out in that case, in line with ExecUpdate's treatment of similar cases.
* This can happen if an UPDATE is triggered from within ExecQual(),
* ExecWithCheckOptions() or ExecProject() above, e.g. by selecting from a
* wCTE in the ON CONFLICT's SET.
*/
/* Execute UPDATE with projection */
*returning = ExecUpdate(mtstate, &tuple.t_self, NULL,
mtstate->mt_conflproj, planSlot,
&mtstate->mt_epqstate, mtstate->ps.state,
canSetTag);
ReleaseBuffer(buffer);
return true;
}
12、InstrCountTuples2
/* Macros for inline access to certain instrumentation counters */
#define InstrCountTuples2(node, delta) \
do { \
if (((PlanState *)(node))->instrument) \
((PlanState *)(node))->instrument->ntuples2 += (delta); \
} while (0)
13、ExecCheckTIDVisible
/*
* ExecCheckTIDVisible -- convenience variant of ExecCheckHeapTupleVisible()
*/
static void
ExecCheckTIDVisible(EState *estate,
ResultRelInfo *relinfo,
ItemPointer tid)
{
Relation rel = relinfo->ri_RelationDesc;
Buffer buffer;
HeapTupleData tuple;
/* Redundantly check isolation level */
if (!IsolationUsesXactSnapshot())
return;
tuple.t_self = *tid;
if (!heap_fetch(rel, SnapshotAny, &tuple, &buffer, false, NULL))
elog(ERROR, "failed to fetch conflicting tuple for ON CONFLICT");
ExecCheckHeapTupleVisible(estate, &tuple, buffer);
ReleaseBuffer(buffer);
}
14、SpeculativeInsertionLockAcquire
/*
* SpeculativeInsertionLockAcquire
*
* Insert a lock showing that the given transaction ID is inserting a tuple,
* but hasn't yet decided whether it's going to keep it. The lock can then be
* used to wait for the decision to go ahead with the insertion, or aborting
* it.
*
* The token is used to distinguish multiple insertions by the same
* transaction. It is returned to caller.
*/
uint32
SpeculativeInsertionLockAcquire(TransactionId xid)
{
LOCKTAG tag;
speculativeInsertionToken++;
/*
* Check for wrap-around. Zero means no token is held, so don't use that.
*/
if (speculativeInsertionToken == 0)
speculativeInsertionToken = 1;
SET_LOCKTAG_SPECULATIVE_INSERTION(tag, xid, speculativeInsertionToken);
(void) LockAcquire(&tag, ExclusiveLock, false, false);
return speculativeInsertionToken;
}
15、HeapTupleHeaderSetSpeculativeToken
#define HeapTupleHeaderSetSpeculativeToken(tup, token) \ ( \ ItemPointerSet(&(tup)->t_ctid, token, SpecTokenOffsetNumber) \ )
16、heap_insert
//上一节已介绍
17、ExecInsertIndexTuples
/* ----------------------------------------------------------------
* ExecInsertIndexTuples
*
* This routine takes care of inserting index tuples
* into all the relations indexing the result relation
* when a heap tuple is inserted into the result relation.
*
* Unique and exclusion constraints are enforced at the same
* time. This returns a list of index OIDs for any unique or
* exclusion constraints that are deferred and that had
* potential (unconfirmed) conflicts. (if noDupErr == true,
* the same is done for non-deferred constraints, but report
* if conflict was speculative or deferred conflict to caller)
*
* If 'arbiterIndexes' is nonempty, noDupErr applies only to
* those indexes. NIL means noDupErr applies to all indexes.
*
* CAUTION: this must not be called for a HOT update.
* We can't defend against that here for lack of info.
* Should we change the API to make it safer?
* ----------------------------------------------------------------
*/
List *
ExecInsertIndexTuples(TupleTableSlot *slot,
ItemPointer tupleid,
EState *estate,
bool noDupErr,
bool *specConflict,
List *arbiterIndexes)
{
List *result = NIL;
ResultRelInfo *resultRelInfo;
int i;
int numIndices;
RelationPtr relationDescs;
Relation heapRelation;
IndexInfo **indexInfoArray;
ExprContext *econtext;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
/*
* Get information from the result relation info structure.
*/
resultRelInfo = estate->es_result_relation_info;
numIndices = resultRelInfo->ri_NumIndices;
relationDescs = resultRelInfo->ri_IndexRelationDescs;
indexInfoArray = resultRelInfo->ri_IndexRelationInfo;
heapRelation = resultRelInfo->ri_RelationDesc;
/*
* We will use the EState's per-tuple context for evaluating predicates
* and index expressions (creating it if it's not already there).
*/
econtext = GetPerTupleExprContext(estate);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/*
* for each index, form and insert the index tuple
*/
for (i = 0; i < numIndices; i++)
{
Relation indexRelation = relationDescs[i];
IndexInfo *indexInfo;
bool applyNoDupErr;
IndexUniqueCheck checkUnique;
bool satisfiesConstraint;
if (indexRelation == NULL)
continue;
indexInfo = indexInfoArray[i];
/* If the index is marked as read-only, ignore it */
if (!indexInfo->ii_ReadyForInserts)
continue;
/* Check for partial index */
if (indexInfo->ii_Predicate != NIL)
{
ExprState *predicate;
/*
* If predicate state not set up yet, create it (in the estate's
* per-query context)
*/
predicate = indexInfo->ii_PredicateState;
if (predicate == NULL)
{
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
indexInfo->ii_PredicateState = predicate;
}
/* Skip this index-update if the predicate isn't satisfied */
if (!ExecQual(predicate, econtext))
continue;
}
/*
* FormIndexDatum fills in its values and isnull parameters with the
* appropriate values for the column(s) of the index.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/* Check whether to apply noDupErr to this index */
applyNoDupErr = noDupErr &&
(arbiterIndexes == NIL ||
list_member_oid(arbiterIndexes,
indexRelation->rd_index->indexrelid));
/*
* The index AM does the actual insertion, plus uniqueness checking.
*
* For an immediate-mode unique index, we just tell the index AM to
* throw error if not unique.
*
* For a deferrable unique index, we tell the index AM to just detect
* possible non-uniqueness, and we add the index OID to the result
* list if further checking is needed.
*
* For a speculative insertion (used by INSERT ... ON CONFLICT), do
* the same as for a deferrable unique index.
*/
if (!indexRelation->rd_index->indisunique)
checkUnique = UNIQUE_CHECK_NO;
else if (applyNoDupErr)
checkUnique = UNIQUE_CHECK_PARTIAL;
else if (indexRelation->rd_index->indimmediate)
checkUnique = UNIQUE_CHECK_YES;
else
checkUnique = UNIQUE_CHECK_PARTIAL;
satisfiesConstraint =
index_insert(indexRelation, /* index relation */
values, /* array of index Datums */
isnull, /* null flags */
tupleid, /* tid of heap tuple */
heapRelation, /* heap relation */
checkUnique, /* type of uniqueness check to do */
indexInfo); /* index AM may need this */
/*
* If the index has an associated exclusion constraint, check that.
* This is simpler than the process for uniqueness checks since we
* always insert first and then check. If the constraint is deferred,
* we check now anyway, but don't throw error on violation or wait for
* a conclusive outcome from a concurrent insertion; instead we'll
* queue a recheck event. Similarly, noDupErr callers (speculative
* inserters) will recheck later, and wait for a conclusive outcome
* then.
*
* An index for an exclusion constraint can't also be UNIQUE (not an
* essential property, we just don't allow it in the grammar), so no
* need to preserve the prior state of satisfiesConstraint.
*/
if (indexInfo->ii_ExclusionOps != NULL)
{
bool violationOK;
CEOUC_WAIT_MODE waitMode;
if (applyNoDupErr)
{
violationOK = true;
waitMode = CEOUC_LIVELOCK_PREVENTING_WAIT;
}
else if (!indexRelation->rd_index->indimmediate)
{
violationOK = true;
waitMode = CEOUC_NOWAIT;
}
else
{
violationOK = false;
waitMode = CEOUC_WAIT;
}
satisfiesConstraint =
check_exclusion_or_unique_constraint(heapRelation,
indexRelation, indexInfo,
tupleid, values, isnull,
estate, false,
waitMode, violationOK, NULL);
}
if ((checkUnique == UNIQUE_CHECK_PARTIAL ||
indexInfo->ii_ExclusionOps != NULL) &&
!satisfiesConstraint)
{
/*
* The tuple potentially violates the uniqueness or exclusion
* constraint, so make a note of the index so that we can re-check
* it later. Speculative inserters are told if there was a
* speculative conflict, since that always requires a restart.
*/
result = lappend_oid(result, RelationGetRelid(indexRelation));
if (indexRelation->rd_index->indimmediate && specConflict)
*specConflict = true;
}
}
return result;
}
18、heap_finish_speculative
/*
* heap_finish_speculative - mark speculative insertion as successful
*
* To successfully finish a speculative insertion we have to clear speculative
* token from tuple. To do so the t_ctid field, which will contain a
* speculative token value, is modified in place to point to the tuple itself,
* which is characteristic of a newly inserted ordinary tuple.
*
* NB: It is not ok to commit without either finishing or aborting a
* speculative insertion. We could treat speculative tuples of committed
* transactions implicitly as completed, but then we would have to be prepared
* to deal with speculative tokens on committed tuples. That wouldn't be
* difficult - no-one looks at the ctid field of a tuple with invalid xmax -
* but clearing the token at completion isn't very expensive either.
* An explicit confirmation WAL record also makes logical decoding simpler.
*/
void
heap_finish_speculative(Relation relation, HeapTuple tuple)
{
Buffer buffer;
Page page;
OffsetNumber offnum;
ItemId lp = NULL;
HeapTupleHeader htup;
buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(&(tuple->t_self)));
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
page = (Page) BufferGetPage(buffer);
offnum = ItemPointerGetOffsetNumber(&(tuple->t_self));
if (PageGetMaxOffsetNumber(page) >= offnum)
lp = PageGetItemId(page, offnum);
if (PageGetMaxOffsetNumber(page) < offnum || !ItemIdIsNormal(lp))
elog(ERROR, "invalid lp");
htup = (HeapTupleHeader) PageGetItem(page, lp);
/* SpecTokenOffsetNumber should be distinguishable from any real offset */
StaticAssertStmt(MaxOffsetNumber < SpecTokenOffsetNumber,
"invalid speculative token constant");
/* NO EREPORT(ERROR) from here till changes are logged */
START_CRIT_SECTION();
Assert(HeapTupleHeaderIsSpeculative(tuple->t_data));
MarkBufferDirty(buffer);
/*
* Replace the speculative insertion token with a real t_ctid, pointing to
* itself like it does on regular tuples.
*/
htup->t_ctid = tuple->t_self;
/* XLOG stuff */
if (RelationNeedsWAL(relation))
{
xl_heap_confirm xlrec;
XLogRecPtr recptr;
xlrec.offnum = ItemPointerGetOffsetNumber(&tuple->t_self);
XLogBeginInsert();
/* We want the same filtering on this as on a plain insert */
XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
XLogRegisterData((char *) &xlrec, SizeOfHeapConfirm);
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_CONFIRM);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
UnlockReleaseBuffer(buffer);
}
19、heap_abort_speculative
/*
* heap_abort_speculative - kill a speculatively inserted tuple
*
* Marks a tuple that was speculatively inserted in the same command as dead,
* by setting its xmin as invalid. That makes it immediately appear as dead
* to all transactions, including our own. In particular, it makes
* HeapTupleSatisfiesDirty() regard the tuple as dead, so that another backend
* inserting a duplicate key value won't unnecessarily wait for our whole
* transaction to finish (it'll just wait for our speculative insertion to
* finish).
*
* Killing the tuple prevents "unprincipled deadlocks", which are deadlocks
* that arise due to a mutual dependency that is not user visible. By
* definition, unprincipled deadlocks cannot be prevented by the user
* reordering lock acquisition in client code, because the implementation level
* lock acquisitions are not under the user's direct control. If speculative
* inserters did not take this precaution, then under high concurrency they
* could deadlock with each other, which would not be acceptable.
*
* This is somewhat redundant with heap_delete, but we prefer to have a
* dedicated routine with stripped down requirements. Note that this is also
* used to delete the TOAST tuples created during speculative insertion.
*
* This routine does not affect logical decoding as it only looks at
* confirmation records.
*/
void
heap_abort_speculative(Relation relation, HeapTuple tuple)
{
TransactionId xid = GetCurrentTransactionId();
ItemPointer tid = &(tuple->t_self);
ItemId lp;
HeapTupleData tp;
Page page;
BlockNumber block;
Buffer buffer;
Assert(ItemPointerIsValid(tid));
block = ItemPointerGetBlockNumber(tid);
buffer = ReadBuffer(relation, block);
page = BufferGetPage(buffer);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
/*
* Page can't be all visible, we just inserted into it, and are still
* running.
*/
Assert(!PageIsAllVisible(page));
lp = PageGetItemId(page, ItemPointerGetOffsetNumber(tid));
Assert(ItemIdIsNormal(lp));
tp.t_tableOid = RelationGetRelid(relation);
tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
tp.t_len = ItemIdGetLength(lp);
tp.t_self = *tid;
/*
* Sanity check that the tuple really is a speculatively inserted tuple,
* inserted by us.
*/
if (tp.t_data->t_choice.t_heap.t_xmin != xid)
elog(ERROR, "attempted to kill a tuple inserted by another transaction");
if (!(IsToastRelation(relation) || HeapTupleHeaderIsSpeculative(tp.t_data)))
elog(ERROR, "attempted to kill a non-speculative tuple");
Assert(!HeapTupleHeaderIsHeapOnly(tp.t_data));
/*
* No need to check for serializable conflicts here. There is never a
* need for a combocid, either. No need to extract replica identity, or
* do anything special with infomask bits.
*/
START_CRIT_SECTION();
/*
* The tuple will become DEAD immediately. Flag that this page
* immediately is a candidate for pruning by setting xmin to
* RecentGlobalXmin. That's not pretty, but it doesn't seem worth
* inventing a nicer API for this.
*/
Assert(TransactionIdIsValid(RecentGlobalXmin));
PageSetPrunable(page, RecentGlobalXmin);
/* store transaction information of xact deleting the tuple */
tp.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
tp.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
/*
* Set the tuple header xmin to InvalidTransactionId. This makes the
* tuple immediately invisible everyone. (In particular, to any
* transactions waiting on the speculative token, woken up later.)
*/
HeapTupleHeaderSetXmin(tp.t_data, InvalidTransactionId);
/* Clear the speculative insertion token too */
tp.t_data->t_ctid = tp.t_self;
MarkBufferDirty(buffer);
/*
* XLOG stuff
*
* The WAL records generated here match heap_delete(). The same recovery
* routines are used.
*/
if (RelationNeedsWAL(relation))
{
xl_heap_delete xlrec;
XLogRecPtr recptr;
xlrec.flags = XLH_DELETE_IS_SUPER;
xlrec.infobits_set = compute_infobits(tp.t_data->t_infomask,
tp.t_data->t_infomask2);
xlrec.offnum = ItemPointerGetOffsetNumber(&tp.t_self);
xlrec.xmax = xid;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfHeapDelete);
XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
/* No replica identity & replication origin logged */
recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_DELETE);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
if (HeapTupleHasExternal(&tp))
{
Assert(!IsToastRelation(relation));
toast_delete(relation, &tp, true);
}
/*
* Never need to mark tuple for invalidation, since catalogs don't support
* speculative insertion
*/
/* Now we can release the buffer */
ReleaseBuffer(buffer);
/* count deletion, as we counted the insertion too */
pgstat_count_heap_delete(relation);
}
20、SpeculativeInsertionLockRelease
/*
* SpeculativeInsertionLockRelease
*
* Delete the lock showing that the given transaction is speculatively
* inserting a tuple.
*/
void
SpeculativeInsertionLockRelease(TransactionId xid)
{
LOCKTAG tag;
SET_LOCKTAG_SPECULATIVE_INSERTION(tag, xid, speculativeInsertionToken);
LockRelease(&tag, ExclusiveLock, false);
}
21、list_free
/*
* Free all the cells of the list, as well as the list itself. Any
* objects that are pointed-to by the cells of the list are NOT
* free'd.
*
* On return, the argument to this function has been freed, so the
* caller would be wise to set it to NIL for safety's sake.
*/
void
list_free(List *list)
{
list_free_private(list, false);
}
/*
* Free all storage in a list, and optionally the pointed-to elements
*/
static void
list_free_private(List *list, bool deep)
{
ListCell *cell;
check_list_invariants(list);
cell = list_head(list);
while (cell != NULL)
{
ListCell *tmp = cell;
cell = lnext(cell);
if (deep)
pfree(lfirst(tmp));
pfree(tmp);
}
if (list)
pfree(list);
}
22、setLastTid
void
setLastTid(const ItemPointer tid)
{
Current_last_tid = *tid;
}
23、ExecARUpdateTriggers
void
ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
ItemPointer tupleid,
HeapTuple fdw_trigtuple,
HeapTuple newtuple,
List *recheckIndexes,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if ((trigdesc && trigdesc->trig_update_after_row) ||
(transition_capture &&
(transition_capture->tcs_update_old_table ||
transition_capture->tcs_update_new_table)))
{
HeapTuple trigtuple;
/*
* Note: if the UPDATE is converted into a DELETE+INSERT as part of
* update-partition-key operation, then this function is also called
* separately for DELETE and INSERT to capture transition table rows.
* In such case, either old tuple or new tuple can be NULL.
*/
if (fdw_trigtuple == NULL && ItemPointerIsValid(tupleid))
trigtuple = GetTupleForTrigger(estate,
NULL,
relinfo,
tupleid,
LockTupleExclusive,
NULL);
else
trigtuple = fdw_trigtuple;
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_UPDATE,
true, trigtuple, newtuple, recheckIndexes,
GetUpdatedColumns(relinfo, estate),
transition_capture);
if (trigtuple != fdw_trigtuple)
heap_freetuple(trigtuple);
}
}
24、ExecARInsertTriggers
void
ExecARInsertTriggers(EState *estate, ResultRelInfo *relinfo,
HeapTuple trigtuple, List *recheckIndexes,
TransitionCaptureState *transition_capture)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
if ((trigdesc && trigdesc->trig_insert_after_row) ||
(transition_capture && transition_capture->tcs_insert_new_table))
AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_INSERT,
true, NULL, trigtuple,
recheckIndexes, NULL,
transition_capture);
}
25、ExecProcessReturning
/*
* ExecProcessReturning --- evaluate a RETURNING list
*
* resultRelInfo: current result rel
* tupleSlot: slot holding tuple actually inserted/updated/deleted
* planSlot: slot holding tuple returned by top subplan node
*
* Note: If tupleSlot is NULL, the FDW should have already provided econtext's
* scan tuple.
*
* Returns a slot holding the result tuple
*/
static TupleTableSlot *
ExecProcessReturning(ResultRelInfo *resultRelInfo,
TupleTableSlot *tupleSlot,
TupleTableSlot *planSlot)
{
ProjectionInfo *projectReturning = resultRelInfo->ri_projectReturning;
ExprContext *econtext = projectReturning->pi_exprContext;
/*
* Reset per-tuple memory context to free any expression evaluation
* storage allocated in the previous cycle.
*/
ResetExprContext(econtext);
/* Make tuple and any needed join variables available to ExecProject */
if (tupleSlot)
econtext->ecxt_scantuple = tupleSlot;
else
{
HeapTuple tuple;
/*
* RETURNING expressions might reference the tableoid column, so
* initialize t_tableOid before evaluating them.
*/
Assert(!TupIsNull(econtext->ecxt_scantuple));
tuple = ExecMaterializeSlot(econtext->ecxt_scantuple);
tuple->t_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
}
econtext->ecxt_outertuple = planSlot;
/* Compute the RETURNING expressions */
return ExecProject(projectReturning);
}
二、源码解读
这部分源码需要二次解读（2018-8-6 Mark）
/* ----------------------------------------------------------------
* ExecInsert
*
* For INSERT, we have to insert the tuple into the target relation
* and insert appropriate tuples into the index relations.
*
* Returns RETURNING result if any, otherwise NULL.
* ----------------------------------------------------------------
*/
/*
输入：
mtstate-存储“更新”数据表（包括INSERT, UPDATE, or DELETE）时的状态
slot-执行器使用Tuple Table存储Tuples，每个Tuple存储在该Table的一个Tuple Slot中
planSlot-TODO
estate-管理Executor调用的工作状态
canSetTag-TODO
输出：
TupleTableSlot-相应的Tuple的Slot
*/
static TupleTableSlot *
ExecInsert(ModifyTableState *mtstate,
TupleTableSlot *slot,
TupleTableSlot *planSlot,
EState *estate,
bool canSetTag)
{
HeapTuple tuple;//要插入的tuple
ResultRelInfo *resultRelInfo;//执行更新操作时Relation相关的所有信息
Relation resultRelationDesc;//目标Relation信息
Oid newId;//数据表Oid
List *recheckIndexes = NIL;//需要检查的Index的列表
TupleTableSlot *result = NULL;//结果Tuple对应的Slot
TransitionCaptureState *ar_insert_trig_tcs;//TODO
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;//更新表Node
OnConflictAction onconflict = node->onConflictAction;//冲突处理
/*
* get the heap tuple out of the tuple table slot, making sure we have a
* writable copy
*/
tuple = ExecMaterializeSlot(slot);//"物化"Tuple
/*
* get information on the (current) result relation
*/
//获取Relation相关信息
resultRelInfo = estate->es_result_relation_info;
resultRelationDesc = resultRelInfo->ri_RelationDesc;
/*
* If the result relation has OIDs, force the tuple's OID to zero so that
* heap_insert will assign a fresh OID. Usually the OID already will be
* zero at this point, but there are corner cases where the plan tree can
* return a tuple extracted literally from some table with the same
* rowtype.
*
* XXX if we ever wanted to allow users to assign their own OIDs to new
* rows, this'd be the place to do it. For the moment, we make a point of
* doing this before calling triggers, so that a user-supplied trigger
* could hack the OID if desired.
*/
//设置Oid为InvalidOid(0)，在heap_insert时会更新Oid
if (resultRelationDesc->rd_rel->relhasoids)
HeapTupleSetOid(tuple, InvalidOid);
/*
* BEFORE ROW INSERT Triggers.
*
* Note: We fire BEFORE ROW TRIGGERS for every attempted insertion in an
* INSERT ... ON CONFLICT statement. We cannot check for constraint
* violations before firing these triggers, because they can change the
* values to insert. Also, they can run arbitrary user-defined code with
* side-effects that we can't cancel by just not inserting the tuple.
*/
//触发器-TODO
if (resultRelInfo->ri_TrigDesc &&
resultRelInfo->ri_TrigDesc->trig_insert_before_row)
{
slot = ExecBRInsertTriggers(estate, resultRelInfo, slot);
if (slot == NULL) /* "do nothing" */
return NULL;
/* trigger might have changed tuple */
tuple = ExecMaterializeSlot(slot);
}
//触发器-TODO
/* INSTEAD OF ROW INSERT Triggers */
if (resultRelInfo->ri_TrigDesc &&
resultRelInfo->ri_TrigDesc->trig_insert_instead_row)
{
slot = ExecIRInsertTriggers(estate, resultRelInfo, slot);
if (slot == NULL) /* "do nothing" */
return NULL;
/* trigger might have changed tuple */
tuple = ExecMaterializeSlot(slot);
newId = InvalidOid;
}
else if (resultRelInfo->ri_FdwRoutine)//FDW-TODO
{
/*
* insert into foreign table: let the FDW do it
*/
slot = resultRelInfo->ri_FdwRoutine->ExecForeignInsert(estate,
resultRelInfo,
slot,
planSlot);
if (slot == NULL) /* "do nothing" */
return NULL;
/* FDW might have changed tuple */
tuple = ExecMaterializeSlot(slot);
/*
* AFTER ROW Triggers or RETURNING expressions might reference the
* tableoid column, so initialize t_tableOid before evaluating them.
*/
tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
newId = InvalidOid;
}
else//正常数据表
{
WCOKind wco_kind;//With Check Option类型
/*
* Constraints might reference the tableoid column, so initialize
* t_tableOid before evaluating them.
*/
//获取RelationID
tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
/*
* Check any RLS WITH CHECK policies.
*
* Normally we should check INSERT policies. But if the insert is the
* result of a partition key update that moved the tuple to a new
* partition, we should instead check UPDATE policies, because we are
* executing policies defined on the target table, and not those
* defined on the child partitions.
*/
//With Check Option类型：Update OR Insert？
wco_kind = (mtstate->operation == CMD_UPDATE) ?
WCO_RLS_UPDATE_CHECK : WCO_RLS_INSERT_CHECK;
/*
* ExecWithCheckOptions() will skip any WCOs which are not of the kind
* we are looking for at this point.
*/
//执行检查
if (resultRelInfo->ri_WithCheckOptions != NIL)
ExecWithCheckOptions(wco_kind, resultRelInfo, slot, estate);
/*
* Check the constraints of the tuple.
*/
//检查约束
if (resultRelationDesc->rd_att->constr)
ExecConstraints(resultRelInfo, slot, estate);
/*
* Also check the tuple against the partition constraint, if there is
* one; except that if we got here via tuple-routing, we don't need to
* if there's no BR trigger defined on the partition.
*/
//分区表
if (resultRelInfo->ri_PartitionCheck &&
(resultRelInfo->ri_PartitionRoot == NULL ||
(resultRelInfo->ri_TrigDesc &&
resultRelInfo->ri_TrigDesc->trig_insert_before_row)))
ExecPartitionCheck(resultRelInfo, slot, estate, true);
//索引检查
if (onconflict != ONCONFLICT_NONE && resultRelInfo->ri_NumIndices > 0)
{
/* Perform a speculative insertion. */
uint32 specToken;//Token
ItemPointerData conflictTid;//数据行指针
bool specConflict;//冲突声明
List *arbiterIndexes;//相关索引
arbiterIndexes = resultRelInfo->ri_onConflictArbiterIndexes;
/*
* Do a non-conclusive check for conflicts first.
*
* We're not holding any locks yet, so this doesn't guarantee that
* the later insert won't conflict. But it avoids leaving behind
* a lot of canceled speculative insertions, if you run a lot of
* INSERT ON CONFLICT statements that do conflict.
*
* We loop back here if we find a conflict below, either during
* the pre-check, or when we re-check after inserting the tuple
* speculatively.
*/
vlock:
specConflict = false;
if (!ExecCheckIndexConstraints(slot, estate, &conflictTid,
arbiterIndexes))
{
/* committed conflict tuple found */
if (onconflict == ONCONFLICT_UPDATE)
{
/*
* In case of ON CONFLICT DO UPDATE, execute the UPDATE
* part. Be prepared to retry if the UPDATE fails because
* of another concurrent UPDATE/DELETE to the conflict
* tuple.
*/
TupleTableSlot *returning = NULL;
if (ExecOnConflictUpdate(mtstate, resultRelInfo,
&conflictTid, planSlot, slot,
estate, canSetTag, &returning))
{
InstrCountTuples2(&mtstate->ps, 1);
return returning;
}
else
goto vlock;
}
else
{
/*
* In case of ON CONFLICT DO NOTHING, do nothing. However,
* verify that the tuple is visible to the executor's MVCC
* snapshot at higher isolation levels.
*/
Assert(onconflict == ONCONFLICT_NOTHING);
ExecCheckTIDVisible(estate, resultRelInfo, &conflictTid);
InstrCountTuples2(&mtstate->ps, 1);
return NULL;
}
}
/*
* Before we start insertion proper, acquire our "speculative
* insertion lock". Others can use that to wait for us to decide
* if we're going to go ahead with the insertion, instead of
* waiting for the whole transaction to complete.
*/
specToken = SpeculativeInsertionLockAcquire(GetCurrentTransactionId());
HeapTupleHeaderSetSpeculativeToken(tuple->t_data, specToken);
/* insert the tuple, with the speculative token */
newId = heap_insert(resultRelationDesc, tuple,
estate->es_output_cid,
HEAP_INSERT_SPECULATIVE,
NULL);
/* insert index entries for tuple */
recheckIndexes = ExecInsertIndexTuples(slot, &(tuple->t_self),
estate, true, &specConflict,
arbiterIndexes);
/* adjust the tuple's state accordingly */
if (!specConflict)
heap_finish_speculative(resultRelationDesc, tuple);
else
heap_abort_speculative(resultRelationDesc, tuple);
/*
* Wake up anyone waiting for our decision. They will re-check
* the tuple, see that it's no longer speculative, and wait on our
* XID as if this was a regularly inserted tuple all along. Or if
* we killed the tuple, they will see it's dead, and proceed as if
* the tuple never existed.
*/
SpeculativeInsertionLockRelease(GetCurrentTransactionId());
/*
* If there was a conflict, start from the beginning. We'll do
* the pre-check again, which will now find the conflicting tuple
* (unless it aborts before we get there).
*/
if (specConflict)
{
list_free(recheckIndexes);
goto vlock;
}
/* Since there was no insertion conflict, we're done */
}
else//无需Index检查
{
/*
* insert the tuple normally.
*
* Note: heap_insert returns the tid (location) of the new tuple
* in the t_self field.
*/
newId = heap_insert(resultRelationDesc, tuple,
estate->es_output_cid,
0, NULL);//插入数据
/* insert index entries for tuple */
if (resultRelInfo->ri_NumIndices > 0)
recheckIndexes = ExecInsertIndexTuples(slot, &(tuple->t_self),
estate, false, NULL,
NIL);//索引
}
}
if (canSetTag)
{
(estate->es_processed)++;
estate->es_lastoid = newId;
setLastTid(&(tuple->t_self));
}
/*
* If this insert is the result of a partition key update that moved the
* tuple to a new partition, put this row into the transition NEW TABLE,
* if there is one. We need to do this separately for DELETE and INSERT
* because they happen on different tables.
*/
//触发器-TODO
ar_insert_trig_tcs = mtstate->mt_transition_capture;
if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture
&& mtstate->mt_transition_capture->tcs_update_new_table)
{
ExecARUpdateTriggers(estate, resultRelInfo, NULL,
NULL,
tuple,
NULL,
mtstate->mt_transition_capture);
/*
* We've already captured the NEW TABLE row, so make sure any AR
* INSERT trigger fired below doesn't capture it again.
*/
ar_insert_trig_tcs = NULL;
}
/* AFTER ROW INSERT Triggers */
ExecARInsertTriggers(estate, resultRelInfo, tuple, recheckIndexes,
ar_insert_trig_tcs);
list_free(recheckIndexes);
/*
* Check any WITH CHECK OPTION constraints from parent views. We are
* required to do this after testing all constraints and uniqueness
* violations per the SQL spec, so we do it after actually inserting the
* record into the heap and all indexes.
*
* ExecWithCheckOptions will elog(ERROR) if a violation is found, so the
* tuple will never be seen, if it violates the WITH CHECK OPTION.
*
* ExecWithCheckOptions() will skip any WCOs which are not of the kind we
* are looking for at this point.
*/
if (resultRelInfo->ri_WithCheckOptions != NIL)
ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo, slot, estate);
/* Process RETURNING if present */
if (resultRelInfo->ri_projectReturning)
result = ExecProcessReturning(resultRelInfo, slot, planSlot);
return result;
}
三、跟踪分析
添加主键，插入测试数据：
testdb=# -- 获取pid testdb=# select pg_backend_pid(); pg_backend_pid ---------------- 1527 (1 row) testdb=# testdb=# -- 添加主键 testdb=# alter table t_insert add constraint pk_t_insert primary key(id); ALTER TABLE testdb=# insert into t_insert values(12,'12','12','12'); （挂起）
启动gdb
[root@localhost ~]# gdb -p 1527
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-100.el7
Copyright (C) 2013 Free Software Foundation, Inc.
...
(gdb) b ExecInsert
Breakpoint 1 at 0x6c0227: file nodeModifyTable.c, line 273.
#查看输入参数
(gdb) p *mtstate
$1 = {ps = {type = T_ModifyTableState, plan = 0x1257fa0, state = 0x130bf80, ExecProcNode = 0x6c2485 <ExecModifyTable>, ExecProcNodeReal = 0x6c2485 <ExecModifyTable>, instrument = 0x0,
worker_instrument = 0x0, qual = 0x0, lefttree = 0x0, righttree = 0x0, initPlan = 0x0, subPlan = 0x0, chgParam = 0x0, ps_ResultTupleSlot = 0x130d1e0, ps_ExprContext = 0x0, ps_ProjInfo = 0x0,
scandesc = 0x0}, operation = CMD_INSERT, canSetTag = true, mt_done = false, mt_plans = 0x130c4e0, mt_nplans = 1, mt_whichplan = 0, resultRelInfo = 0x130c1c0, rootResultRelInfo = 0x0,
mt_arowmarks = 0x130c4f8, mt_epqstate = {estate = 0x0, planstate = 0x0, origslot = 0x130c950, plan = 0x132de88, arowMarks = 0x0, epqParam = 0}, fireBSTriggers = false, mt_existing = 0x0,
mt_excludedtlist = 0x0, mt_conflproj = 0x0, mt_partition_tuple_routing = 0x0, mt_transition_capture = 0x0, mt_oc_transition_capture = 0x0, mt_per_subplan_tupconv_maps = 0x0}
(gdb) p *(mtstate->ps->plan)
$2 = {type = T_ModifyTable, startup_cost = 0, total_cost = 0.01, plan_rows = 1, plan_width = 136, parallel_aware = false, parallel_safe = false, plan_node_id = 0, targetlist = 0x0, qual = 0x0,
lefttree = 0x0, righttree = 0x0, initPlan = 0x0, extParam = 0x0, allParam = 0x0}
(gdb) p *(mtstate->ps->state)
$3 = {type = T_EState, es_direction = ForwardScanDirection, es_snapshot = 0x1309fa0, es_crosscheck_snapshot = 0x0, es_range_table = 0x132e1f8, es_plannedstmt = 0x1258420,
es_sourceText = 0x1256ef0 "insert into t_insert values(12,'12','12','12');", es_junkFilter = 0x0, es_output_cid = 0, es_result_relations = 0x130c1c0, es_num_result_relations = 1,
es_result_relation_info = 0x130c1c0, es_root_result_relations = 0x0, es_num_root_result_relations = 0, es_tuple_routing_result_relations = 0x0, es_trig_target_relations = 0x0,
es_trig_tuple_slot = 0x130d290, es_trig_oldtup_slot = 0x0, es_trig_newtup_slot = 0x0, es_param_list_info = 0x0, es_param_exec_vals = 0x130c190, es_queryEnv = 0x0, es_query_cxt = 0x130be70,
es_tupleTable = 0x130c810, es_rowMarks = 0x0, es_processed = 0, es_lastoid = 0, es_top_eflags = 0, es_instrument = 0, es_finished = false, es_exprcontexts = 0x130c7b0, es_subplanstates = 0x0,
es_auxmodifytables = 0x0, es_per_tuple_exprcontext = 0x0, es_epqTuple = 0x0, es_epqTupleSet = 0x0, es_epqScanDone = 0x0, es_use_parallel_mode = false, es_query_dsa = 0x0, es_jit_flags = 0,
es_jit = 0x0}
(gdb) p *(mtstate->ps->ps_ResultTupleSlot)
$4 = {type = T_TupleTableSlot, tts_isempty = true, tts_shouldFree = false, tts_shouldFreeMin = false, tts_slow = false, tts_tuple = 0x0, tts_tupleDescriptor = 0x130d1b0, tts_mcxt = 0x130be70,
tts_buffer = 0, tts_nvalid = 0, tts_values = 0x130d240, tts_isnull = 0x130d240, tts_mintuple = 0x0, tts_minhdr = {t_len = 0, t_self = {ip_blkid = {bi_hi = 0, bi_lo = 0}, ip_posid = 0},
t_tableOid = 0, t_data = 0x0}, tts_off = 0, tts_fixedTupleDescriptor = true}
(gdb) p *(mtstate->ps->ps_ResultTupleSlot->tts_tupleDescriptor)
$5 = {natts = 0, tdtypeid = 2249, tdtypmod = -1, tdhasoid = false, tdrefcount = -1, constr = 0x0, attrs = 0x130d1d0}
(gdb) p *(mtstate->ps->ps_ResultTupleSlot->tts_tupleDescriptor->attrs)
$6 = {attrelid = 128, attname = {
data = "\000\000\000\000p\276\060\001\000\000\000\000\b\000\000\000\001", '\000' <repeats 11 times>, "\260\321\060\001\000\000\000\000p\276\060\001", '\000' <repeats 12 times>, "@\322\060\001\000\000\000\000@\322\060\001"}, atttypid = 0, attstattarget = 0, attlen = 0, attnum = 0, attndims = 0, attcacheoff = 0, atttypmod = 0, attbyval = false, attstorage = 0 '\000', attalign = 0 '\000',
attnotnull = false, atthasdef = false, atthasmissing = false, attidentity = 0 '\000', attisdropped = false, attislocal = false, attinhcount = 0, attcollation = 1}
$7 = (PlanState *) 0x130c560
(gdb) p **(mtstate->mt_plans)
$8 = {type = T_ResultState, plan = 0x132de88, state = 0x130bf80, ExecProcNode = 0x6c5094 <ExecResult>, ExecProcNodeReal = 0x6c5094 <ExecResult>, instrument = 0x0, worker_instrument = 0x0, qual = 0x0,
lefttree = 0x0, righttree = 0x0, initPlan = 0x0, subPlan = 0x0, chgParam = 0x0, ps_ResultTupleSlot = 0x130c950, ps_ExprContext = 0x130c670, ps_ProjInfo = 0x130c700, scandesc = 0x0}
(gdb) p **(mtstate->resultRelInfo)
Structure has no component named operator*.
(gdb) p *(mtstate->resultRelInfo)
$9 = {type = T_ResultRelInfo, ri_RangeTableIndex = 1, ri_RelationDesc = 0x7f2af957d9e8, ri_NumIndices = 1, ri_IndexRelationDescs = 0x130c7e0, ri_IndexRelationInfo = 0x130c7f8, ri_TrigDesc = 0x0,
ri_TrigFunctions = 0x0, ri_TrigWhenExprs = 0x0, ri_TrigInstrument = 0x0, ri_FdwRoutine = 0x0, ri_FdwState = 0x0, ri_usesFdwDirectModify = false, ri_WithCheckOptions = 0x0,
ri_WithCheckOptionExprs = 0x0, ri_ConstraintExprs = 0x0, ri_junkFilter = 0x0, ri_returningList = 0x0, ri_projectReturning = 0x0, ri_onConflictArbiterIndexes = 0x0, ri_onConflict = 0x0,
ri_PartitionCheck = 0x0, ri_PartitionCheckExpr = 0x0, ri_PartitionRoot = 0x0, ri_PartitionReadyForRouting = false}
(gdb) p *(mtstate->resultRelInfo->ri_RelationDesc)
$10 = {rd_node = {spcNode = 1663, dbNode = 16477, relNode = 26731}, rd_smgr = 0x0, rd_refcnt = 1, rd_backend = -1, rd_islocaltemp = false, rd_isnailed = false, rd_isvalid = true,
rd_indexvalid = 1 '\001', rd_statvalid = false, rd_createSubid = 0, rd_newRelfilenodeSubid = 0, rd_rel = 0x7f2af94c31a8, rd_att = 0x7f2af957f6e8, rd_id = 26731, rd_lockInfo = {lockRelId = {
relId = 26731, dbId = 16477}}, rd_rules = 0x0, rd_rulescxt = 0x0, trigdesc = 0x0, rd_rsdesc = 0x0, rd_fkeylist = 0x0, rd_fkeyvalid = false, rd_partkeycxt = 0x0, rd_partkey = 0x0, rd_pdcxt = 0x0,
rd_partdesc = 0x0, rd_partcheck = 0x0, rd_indexlist = 0x7f2af94c2818, rd_oidindex = 0, rd_pkindex = 26737, rd_replidindex = 26737, rd_statlist = 0x0, rd_indexattr = 0x0, rd_projindexattr = 0x0,
rd_keyattr = 0x0, rd_pkattr = 0x0, rd_idattr = 0x0, rd_projidx = 0x0, rd_pubactions = 0x0, rd_options = 0x0, rd_index = 0x0, rd_indextuple = 0x0, rd_amhandler = 0, rd_indexcxt = 0x0,
rd_amroutine = 0x0, rd_opfamily = 0x0, rd_opcintype = 0x0, rd_support = 0x0, rd_supportinfo = 0x0, rd_indoption = 0x0, rd_indexprs = 0x0, rd_indpred = 0x0, rd_exclops = 0x0, rd_exclprocs = 0x0,
rd_exclstrats = 0x0, rd_amcache = 0x0, rd_indcollation = 0x0, rd_fdwroutine = 0x0, rd_toastoid = 0, pgstat_info = 0x12d5850}
(gdb)
#第2个参数slot
(gdb) p *slot
$11 = {type = T_TupleTableSlot, tts_isempty = false, tts_shouldFree = false, tts_shouldFreeMin = false, tts_slow = false, tts_tuple = 0x0, tts_tupleDescriptor = 0x130cb70, tts_mcxt = 0x130be70,
tts_buffer = 0, tts_nvalid = 4, tts_values = 0x130c9b0, tts_isnull = 0x130c9d0, tts_mintuple = 0x0, tts_minhdr = {t_len = 0, t_self = {ip_blkid = {bi_hi = 0, bi_lo = 0}, ip_posid = 0},
t_tableOid = 0, t_data = 0x0}, tts_off = 0, tts_fixedTupleDescriptor = true}
(gdb) p *(slot->tts_tupleDescriptor)
$12 = {natts = 4, tdtypeid = 2249, tdtypmod = -1, tdhasoid = false, tdrefcount = -1, constr = 0x0, attrs = 0x130cb90}
(gdb) p *(slot->tts_values)
$13 = 12
(gdb) p *(slot->tts_isnull)
$14 = false
#参数planSlot
(gdb) p *planSlot
$15 = {type = T_TupleTableSlot, tts_isempty = false, tts_shouldFree = false, tts_shouldFreeMin = false, tts_slow = false, tts_tuple = 0x0, tts_tupleDescriptor = 0x130cb70, tts_mcxt = 0x130be70,
tts_buffer = 0, tts_nvalid = 4, tts_values = 0x130c9b0, tts_isnull = 0x130c9d0, tts_mintuple = 0x0, tts_minhdr = {t_len = 0, t_self = {ip_blkid = {bi_hi = 0, bi_lo = 0}, ip_posid = 0},
t_tableOid = 0, t_data = 0x0}, tts_off = 0, tts_fixedTupleDescriptor = true}
(gdb) p *(planSlot->tts_mcxt)
$16 = {type = T_AllocSetContext, isReset = false, allowInCritSection = false, methods = 0xb8c720 <AllocSetMethods>, parent = 0x131f150, firstchild = 0x130fe90, prevchild = 0x0, nextchild = 0x0,
name = 0xb1a840 "ExecutorState", ident = 0x0, reset_cbs = 0x0}
#参数estate
(gdb) p *estate
$17 = {type = T_EState, es_direction = ForwardScanDirection, es_snapshot = 0x1309fa0, es_crosscheck_snapshot = 0x0, es_range_table = 0x132e1f8, es_plannedstmt = 0x1258420,
es_sourceText = 0x1256ef0 "insert into t_insert values(12,'12','12','12');", es_junkFilter = 0x0, es_output_cid = 0, es_result_relations = 0x130c1c0, es_num_result_relations = 1,
es_result_relation_info = 0x130c1c0, es_root_result_relations = 0x0, es_num_root_result_relations = 0, es_tuple_routing_result_relations = 0x0, es_trig_target_relations = 0x0,
es_trig_tuple_slot = 0x130d290, es_trig_oldtup_slot = 0x0, es_trig_newtup_slot = 0x0, es_param_list_info = 0x0, es_param_exec_vals = 0x130c190, es_queryEnv = 0x0, es_query_cxt = 0x130be70,
es_tupleTable = 0x130c810, es_rowMarks = 0x0, es_processed = 0, es_lastoid = 0, es_top_eflags = 0, es_instrument = 0, es_finished = false, es_exprcontexts = 0x130c7b0, es_subplanstates = 0x0,
es_auxmodifytables = 0x0, es_per_tuple_exprcontext = 0x0, es_epqTuple = 0x0, es_epqTupleSet = 0x0, es_epqScanDone = 0x0, es_use_parallel_mode = false, es_query_dsa = 0x0, es_jit_flags = 0,
es_jit = 0x0}
(gdb) p *(estate->es_snapshot)
$18 = {satisfies = 0x9f73fc <HeapTupleSatisfiesMVCC>, xmin = 1612861, xmax = 1612861, xip = 0x0, xcnt = 0, subxip = 0x0, subxcnt = 0, suboverflowed = false, takenDuringRecovery = false, copied = true,
curcid = 0, speculativeToken = 0, active_count = 1, regd_count = 2, ph_node = {first_child = 0xe7bac0 <CatalogSnapshotData+64>, next_sibling = 0x0, prev_or_parent = 0x0}, whenTaken = 0, lsn = 0}
(gdb)
#参数canSetTag
(gdb) p canSetTag
$19 = true
#进入函数内部
(gdb) next
274 TupleTableSlot *result = NULL;
(gdb)
276 ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
(gdb) p *node
$20 = {plan = {type = 1005513616, startup_cost = 3.502247076882698e-317, total_cost = 9.8678822363083824e-317, plan_rows = 4.1888128009757547e-314, plan_width = 3, parallel_aware = 253,
parallel_safe = 127, plan_node_id = 10076823, targetlist = 0x686b0000405d, qual = 0x130c2d0, lefttree = 0x0, righttree = 0x130c1c0, initPlan = 0x6c2485 <ExecModifyTable>, extParam = 0x0,
allParam = 0x7ffd3beeeb50}, operation = 6923989, canSetTag = false, nominalRelation = 4183284200, partitioned_rels = 0x130c1c0, partColsUpdated = 128, resultRelations = 0x1257fa0,
resultRelIndex = 19974480, rootResultRelIndex = 0, plans = 0x0, withCheckOptionLists = 0x33beeeb50, returningLists = 0x130bf80, fdwPrivLists = 0x0, fdwDirectModifyPlans = 0x130c2d0, rowMarks = 0x0,
epqParam = 0, onConflictAction = ONCONFLICT_NONE, arbiterIndexes = 0x130c950, onConflictSet = 0x0, onConflictWhere = 0x130c560, exclRelRTI = 19972544, exclRelTlist = 0x0}
(gdb)
(gdb) p onconflict
$21 = ONCONFLICT_NONE
...
(gdb) next
289 resultRelationDesc = resultRelInfo->ri_RelationDesc;
(gdb) p *resultRelInfo
$26 = {type = T_ResultRelInfo, ri_RangeTableIndex = 1, ri_RelationDesc = 0x7f2af957d9e8, ri_NumIndices = 1, ri_IndexRelationDescs = 0x130c7e0, ri_IndexRelationInfo = 0x130c7f8, ri_TrigDesc = 0x0,
ri_TrigFunctions = 0x0, ri_TrigWhenExprs = 0x0, ri_TrigInstrument = 0x0, ri_FdwRoutine = 0x0, ri_FdwState = 0x0, ri_usesFdwDirectModify = false, ri_WithCheckOptions = 0x0,
ri_WithCheckOptionExprs = 0x0, ri_ConstraintExprs = 0x0, ri_junkFilter = 0x0, ri_returningList = 0x0, ri_projectReturning = 0x0, ri_onConflictArbiterIndexes = 0x0, ri_onConflict = 0x0,
ri_PartitionCheck = 0x0, ri_PartitionCheckExpr = 0x0, ri_PartitionRoot = 0x0, ri_PartitionReadyForRouting = false}
(gdb) p *(tuple->t_data)
$27 = {t_choice = {t_heap = {t_xmin = 244, t_xmax = 4294967295, t_field3 = {t_cid = 2249, t_xvac = 2249}}, t_datum = {datum_len_ = 244, datum_typmod = -1, datum_typeid = 2249}}, t_ctid = {ip_blkid = {
bi_hi = 65535, bi_lo = 65535}, ip_posid = 0}, t_infomask2 = 4, t_infomask = 2, t_hoff = 24 '\030', t_bits = 0x130d36f ""}
(gdb) p *(tuple)
$28 = {t_len = 61, t_self = {ip_blkid = {bi_hi = 65535, bi_lo = 65535}, ip_posid = 0}, t_tableOid = 0, t_data = 0x130d358}
(gdb)
(gdb) p *resultRelationDesc
$29 = {rd_node = {spcNode = 1663, dbNode = 16477, relNode = 26731}, rd_smgr = 0x0, rd_refcnt = 1, rd_backend = -1, rd_islocaltemp = false, rd_isnailed = false, rd_isvalid = true,
rd_indexvalid = 1 '\001', rd_statvalid = false, rd_createSubid = 0, rd_newRelfilenodeSubid = 0, rd_rel = 0x7f2af94c31a8, rd_att = 0x7f2af957f6e8, rd_id = 26731, rd_lockInfo = {lockRelId = {
relId = 26731, dbId = 16477}}, rd_rules = 0x0, rd_rulescxt = 0x0, trigdesc = 0x0, rd_rsdesc = 0x0, rd_fkeylist = 0x0, rd_fkeyvalid = false, rd_partkeycxt = 0x0, rd_partkey = 0x0, rd_pdcxt = 0x0,
rd_partdesc = 0x0, rd_partcheck = 0x0, rd_indexlist = 0x7f2af94c2818, rd_oidindex = 0, rd_pkindex = 26737, rd_replidindex = 26737, rd_statlist = 0x0, rd_indexattr = 0x0, rd_projindexattr = 0x0,
rd_keyattr = 0x0, rd_pkattr = 0x0, rd_idattr = 0x0, rd_projidx = 0x0, rd_pubactions = 0x0, rd_options = 0x0, rd_index = 0x0, rd_indextuple = 0x0, rd_amhandler = 0, rd_indexcxt = 0x0,
rd_amroutine = 0x0, rd_opfamily = 0x0, rd_opcintype = 0x0, rd_support = 0x0, rd_supportinfo = 0x0, rd_indoption = 0x0, rd_indexprs = 0x0, rd_indpred = 0x0, rd_exclops = 0x0, rd_exclprocs = 0x0,
rd_exclstrats = 0x0, rd_amcache = 0x0, rd_indcollation = 0x0, rd_fdwroutine = 0x0, rd_toastoid = 0, pgstat_info = 0x12d5850}
#以上，获取了Relation相关的信息
#没有触发器，无需执行触发器相关逻辑
#进入正常数据表的处理逻辑 line 373行
(gdb) next
315 if (resultRelInfo->ri_TrigDesc &&
(gdb) next
328 if (resultRelInfo->ri_TrigDesc &&
(gdb)
341 else if (resultRelInfo->ri_FdwRoutine)
(gdb)
373 tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
(gdb) next
384 wco_kind = (mtstate->operation == CMD_UPDATE) ?
(gdb) next
391 if (resultRelInfo->ri_WithCheckOptions != NIL)
(gdb) p tuple->t_tableOid
$31 = 26731
(gdb) p wco_kind
$32 = WCO_RLS_INSERT_CHECK
#检查约束
(gdb) next
397 if (resultRelationDesc->rd_att->constr)
(gdb)
398 ExecConstraints(resultRelInfo, slot, estate);
(gdb)
#非分区表，无需检查
#进入正常数据插入逻辑
411 if (onconflict != ONCONFLICT_NONE && resultRelInfo->ri_NumIndices > 0)
(gdb)
529 newId = heap_insert(resultRelationDesc, tuple,
(gdb) p resultRelInfo->ri_NumIndices
$33 = 1
(gdb) p onconflict
$34 = ONCONFLICT_NONE
(gdb)
(gdb) next
534 if (resultRelInfo->ri_NumIndices > 0)
(gdb) p newId
$35 = 0
(gdb) next
535 recheckIndexes = ExecInsertIndexTuples(slot, &(tuple->t_self),
(gdb)
541 if (canSetTag)
(gdb)
543 (estate->es_processed)++;
(gdb)
544 estate->es_lastoid = newId;
(gdb)
545 setLastTid(&(tuple->t_self));
(gdb)
554 ar_insert_trig_tcs = mtstate->mt_transition_capture;
(gdb)
555 if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture
(gdb)
572 ExecARInsertTriggers(estate, resultRelInfo, tuple, recheckIndexes,
(gdb)
575 list_free(recheckIndexes);
(gdb)
589 if (resultRelInfo->ri_WithCheckOptions != NIL)
(gdb)
593 if (resultRelInfo->ri_projectReturning)
(gdb)
596 return result;
(gdb)
597 }
#DONE!
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