TokuDB安装及注意事项有哪些

技术TokuDB安装及注意事项有哪些这篇文章将为大家详细讲解有关TokuDB安装及注意事项有哪些,小编觉得挺实用的,因此分享给大家做个参考,希望大家阅读完这篇文章后可以有所收获。TokuDB的特点:1、高压缩比,官方宣称

这篇文章将为大家详细讲解有关TokuDB安装及注意事项有哪些,小编觉得挺实用的,因此分享给大家做个参考,希望大家阅读完这篇文章后可以有所收获。

TokuDB的特点:

1、高压缩比,官方宣称可以达到1:12。

2、高插入性能,官方称至少比innodb高9倍。

3、可以在线添加索引和字段,速度快。

TokuDB的缺点:

1、cpu usr态消耗高

2、响应时间变长。

安装环境:

OS:centos 6.5

IP:192.168.0.103

TokuDB:5.6.29

安装介质:

Percona-Server-shared、Percona-Server-client、Percona-Server-server、Percona-Server-tokudb(注意安装顺序)

安装介质下载:

https://www.percona.com/downloads/Percona-Server-5.6/LATEST/

安装步骤:

1、先安装percona-服务器共享

[root @ linfytest3 Downloads]# rpm-IVH Percona-服务器-共享-56-5。6 .29-rel 76。2 .El 6。x86 _ 64。每分钟转数

警告: Percona-服务器-共享-56-5。6 .29-rel 76。2 .El 6。x86 _ 64。rpm :标头V4每日生活津贴/SHA1签名,密钥ID cd2efd2a: NOKEY

准备的.########################################### [100%]

1: Percona-服务器-共享-5 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 100%]

2、再安装percona-服务器-客户端

[root @ linfytest3 Downloads]# rpm-IVH Percona-服务器-客户端-56-5。6 .29-rel 76。2 .El 6。x86 _ 64。每分钟转数

警告: Percona-服务器-客户端-56-5 .6 .29-rel 76。2 .El 6。x86 _ 64。rpm :标头V4每日生活津贴/SHA1签名,密钥ID cd2efd2a: NOKEY

准备的.########################################### [100%]

1: Percona-服务器-客户端-5 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 100%]

3、再安装percona-服务器-服务器

[root @ linfytest3 Downloads]# rpm-IVH佩科纳-服务器-服务器-56-5。6 .29-rel 76。2 .El 6。x86 _ 64。每分钟转数

警告: Percona-服务器-服务器-56-5。6 .29-rel 76。2 .El 6。x86 _ 64。rpm :标头V4每日生活津贴/SHA1签名,密钥ID cd2efd2a: NOKEY

准备的.########################################### [100%]

1: Percona-Server-Server-5 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # 100%]

2016-05-08 19:36336057 0[警告]不推荐使用带有隐式系统默认值值的时间戳。请使用-explicit _ defaults _ for _时间戳服务器选项(有关更多详细信息,请参见文档)。

从进程3039开始.

使用原子引用计数缓冲区便便

l pages
2016-05-08 19:36:57 3039 [Note] InnoDB: The InnoDB memory heap is disabled
2016-05-08 19:36:57 3039 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2016-05-08 19:36:57 3039 [Note] InnoDB: Memory barrier is not used
2016-05-08 19:36:57 3039 [Note] InnoDB: Compressed tables use zlib 1.2.3
2016-05-08 19:36:57 3039 [Note] InnoDB: Using Linux native AIO
2016-05-08 19:36:57 3039 [Note] InnoDB: Using CPU crc32 instructions
2016-05-08 19:36:57 3039 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2016-05-08 19:36:57 3039 [Note] InnoDB: Completed initialization of buffer pool
2016-05-08 19:36:57 3039 [Note] InnoDB: Highest supported file format is Barracuda.
2016-05-08 19:36:57 3039 [Note] InnoDB: 128 rollback segment(s) are active.
2016-05-08 19:36:57 3039 [Note] InnoDB: Waiting for purge to start
2016-05-08 19:36:57 3039 [Note] InnoDB:  Percona XtraDB (http://www.percona.com) 5.6.29-76.2 started; log sequence number 1600607
2016-05-08 19:36:57 3039 [Note] RSA private key file not found: /var/lib/mysql//private_key.pem. Some authentication plugins will not work.
2016-05-08 19:36:57 3039 [Note] RSA public key file not found: /var/lib/mysql//public_key.pem. Some authentication plugins will not work.
2016-05-08 19:36:58 3039 [Note] Binlog end
2016-05-08 19:36:58 3039 [Note] InnoDB: FTS optimize thread exiting.
2016-05-08 19:36:58 3039 [Note] InnoDB: Starting shutdown...
2016-05-08 19:36:59 3039 [Note] InnoDB: Shutdown completed; log sequence number 1625987

2016-05-08 19:36:59 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2016-05-08 19:36:59 0 [Note] /usr/sbin/mysqld (mysqld 5.6.29-76.2) starting as process 3064 ...
2016-05-08 19:36:59 3064 [Note] InnoDB: Using atomics to ref count buffer pool pages
2016-05-08 19:36:59 3064 [Note] InnoDB: The InnoDB memory heap is disabled
2016-05-08 19:36:59 3064 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2016-05-08 19:36:59 3064 [Note] InnoDB: Memory barrier is not used
2016-05-08 19:36:59 3064 [Note] InnoDB: Compressed tables use zlib 1.2.3
2016-05-08 19:36:59 3064 [Note] InnoDB: Using Linux native AIO
2016-05-08 19:36:59 3064 [Note] InnoDB: Using CPU crc32 instructions
2016-05-08 19:36:59 3064 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2016-05-08 19:36:59 3064 [Note] InnoDB: Completed initialization of buffer pool
2016-05-08 19:37:00 3064 [Note] InnoDB: Highest supported file format is Barracuda.
2016-05-08 19:37:00 3064 [Note] InnoDB: 128 rollback segment(s) are active.
2016-05-08 19:37:00 3064 [Note] InnoDB: Waiting for purge to start
2016-05-08 19:37:00 3064 [Note] InnoDB:  Percona XtraDB (http://www.percona.com) 5.6.29-76.2 started; log sequence number 1625987
2016-05-08 19:37:00 3064 [Note] RSA private key file not found: /var/lib/mysql//private_key.pem. Some authentication plugins will not work.
2016-05-08 19:37:00 3064 [Note] RSA public key file not found: /var/lib/mysql//public_key.pem. Some authentication plugins will not work.
2016-05-08 19:37:00 3064 [Note] Binlog end
2016-05-08 19:37:00 3064 [Note] InnoDB: FTS optimize thread exiting.
2016-05-08 19:37:00 3064 [Note] InnoDB: Starting shutdown...
2016-05-08 19:37:02 3064 [Note] InnoDB: Shutdown completed; log sequence number 1625997

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

  /usr/bin/mysqladmin -u root password 'new-password'
  /usr/bin/mysqladmin -u root -h linfytest3 password 'new-password'

Alternatively you can run:

  /usr/bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default.  This is
strongly recommended for production servers.

See the manual for more instructions.

Please report any problems at
 https://bugs.launchpad.net/percona-server/+filebug

The latest information about Percona Server is available on the web at
  http://www.percona.com/software/percona-server

Support Percona by buying support at
 http://www.percona.com/products/mysql-support

WARNING: Default config file /etc/my.cnf exists on the system
This file will be read by default by the MySQL server
If you do not want to use this, either remove it, or use the
--defaults-file argument to mysqld_safe when starting the server

Percona Server is distributed with several useful UDF (User Defined Function) from Percona Toolkit.
Run the following commands to create these functions:
mysql -e "CREATE FUNCTION fnv1a_64 RETURNS INTEGER SONAME 'libfnv1a_udf.so'"
mysql -e "CREATE FUNCTION fnv_64 RETURNS INTEGER SONAME 'libfnv_udf.so'"
mysql -e "CREATE FUNCTION murmur_hash RETURNS INTEGER SONAME 'libmurmur_udf.so'"
See http://www.percona.com/doc/percona-server/5.6/management/udf_percona_toolkit.html for more details

4、安装jemalloc
[root@linfytest3 Downloads]# rpm -ivh jemalloc-3.6.0-2.el5.x86_64.rpm
Preparing...                ########################################### [100%]
   1:jemalloc               ########################################### [100%]

5、安装Percona-Server-tokudb

[root@linfytest3 Downloads]# rpm -ivh Percona-Server-tokudb-56-5.6.29-rel76.2.el6.x86_64.rpm
warning: Percona-Server-tokudb-56-5.6.29-rel76.2.el6.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID cd2efd2a: NOKEY
Preparing...                ########################################### [100%]
   1:Percona-Server-tokudb-5########################################### [100%]

 * This release of Percona Server is distributed with TokuDB storage engine.
 * Run the following script to enable the TokuDB storage engine in Percona Server:

        ps_tokudb_admin --enable -u <mysql_admin_user> -p[mysql_admin_pass] [-S <socket>] [-h <host> -P <port>]

 * See http://www.percona.com/doc/percona-server/5.6/tokudb/tokudb_installation.html for more installation details

 * See http://www.percona.com/doc/percona-server/5.6/tokudb/tokudb_intro.html for an introduction to TokuDB

6、启动MySQL
 /usr/sbin/mysqld

root@linfytest3 sbin]# ./mysqld -uroot 
2016-05-08 20:21:47 0 [Warning] Ignoring user change to 'root' because the user was set to 'mysql' earlier on the command line

2016-05-08 20:21:47 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2016-05-08 20:21:47 0 [Note] ./mysqld (mysqld 5.6.29-76.2) starting as process 3848 ...
2016-05-08 20:21:47 3848 [Note] Plugin 'FEDERATED' is disabled.
2016-05-08 20:21:47 3848 [Note] InnoDB: Using atomics to ref count buffer pool pages
2016-05-08 20:21:47 3848 [Note] InnoDB: The InnoDB memory heap is disabled
2016-05-08 20:21:47 3848 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2016-05-08 20:21:47 3848 [Note] InnoDB: Memory barrier is not used
2016-05-08 20:21:47 3848 [Note] InnoDB: Compressed tables use zlib 1.2.3
2016-05-08 20:21:47 3848 [Note] InnoDB: Using Linux native AIO
2016-05-08 20:21:47 3848 [Note] InnoDB: Using CPU crc32 instructions
2016-05-08 20:21:47 3848 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2016-05-08 20:21:47 3848 [Note] InnoDB: Completed initialization of buffer pool
2016-05-08 20:21:48 3848 [Note] InnoDB: Highest supported file format is Barracuda.
2016-05-08 20:21:48 3848 [Note] InnoDB: 128 rollback segment(s) are active.
2016-05-08 20:21:48 3848 [Note] InnoDB: Waiting for purge to start
2016-05-08 20:21:48 3848 [Note] InnoDB:  Percona XtraDB (http://www.percona.com) 5.6.29-76.2 started; log sequence number 1626017
2016-05-08 20:21:48 3848 [Note] RSA private key file not found: /var/lib/mysql//private_key.pem. Some authentication plugins will not work.
2016-05-08 20:21:48 3848 [Note] RSA public key file not found: /var/lib/mysql//public_key.pem. Some authentication plugins will not work.
2016-05-08 20:21:48 3848 [Note] Server hostname (bind-address): '*'; port: 3306
2016-05-08 20:21:48 3848 [Note] IPv6 is available.
2016-05-08 20:21:48 3848 [Note]   - '::' resolves to '::';
2016-05-08 20:21:48 3848 [Note] Server socket created on IP: '::'.
2016-05-08 20:21:48 3848 [Note] Event Scheduler: Loaded 0 events
2016-05-08 20:21:48 3848 [Note] ./mysqld: ready for connections.
Version: '5.6.29-76.2'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  Percona Server (GPL), Release 76.2, Revision ddf26fe

7、登录mysql
[root@linfytest3 sbin]# /usr/bin/mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.29-76.2 Percona Server (GPL), Release 76.2, Revision ddf26fe

Copyright (c) 2009-2016 Percona LLC and/or its affiliates
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show engines;
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| Engine             | Support | Comment                                                                    | Transactions | XA   | Savepoints |
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| InnoDB             | DEFAULT | Percona-XtraDB, Supports transactions, row-level locking, and foreign keys | YES          | YES  | YES        |
| CSV                | YES     | CSV storage engine                                                         | NO           | NO   | NO         |
| MyISAM             | YES     | MyISAM storage engine                                                      | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears)             | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables                  | NO           | NO   | NO         |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                                      | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                                     | NO           | NO   | NO         |
| FEDERATED          | NO      | Federated MySQL storage engine                                             | NULL         | NULL | NULL       |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                                         | NO           | NO   | NO         |
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
9 rows in set (0.01 sec)

8、安装tokuDB插件

[root@linfytest3 bin]# /usr/bin/ps_tokudb_admin --enable -u root -P 3848 -p
Enter password:

Checking SELinux status...
ERROR: SELinux is in enforcing mode and needs to be disabled (or put into permissive mode) for TokuDB to work correctly.

[root@linfytest3 bin]# /usr/sbin/sestatus
SELinux status:                 enabled
SELinuxfs mount:                /selinux
Current mode:                   enforcing
Mode from config file:          enforcing
Policy version:                 24
Policy from config file:        targeted
[root@linfytest3 bin]# getenforce
Enforcing

[root@linfytest3 bin]# setenforce 0
[root@linfytest3 bin]# getenforce
Permissive

root@linfytest3 bin]# /usr/bin/ps_tokudb_admin --enable -u root -P 3848 -p
Enter password:

Checking SELinux status...
INFO: SELinux is in permissive mode.

Checking if Percona Server is running with jemalloc enabled...
ERROR: Percona Server is not running with jemalloc, please restart mysql service to enable it and then run this script...

关闭mysql server
/usr/bin/mysqladmin shutdown -uroot -p

启动Mysql server
root@linfytest3 bin]# ./mysqld_safe &
[1] 5579
[root@linfytest3 bin]# 160508 23:42:51 mysqld_safe Adding '/usr/lib64/libjemalloc.so.1' to LD_PRELOAD for mysqld
160508 23:42:51 mysqld_safe Logging to '/var/log/mysqld.log'.
160508 23:42:51 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql

[root@linfytest3 bin]# pwd
/usr/bin

[root@linfytest3 bin]# /usr/bin/ps_tokudb_admin --enable -u root -P 5579 -p
Enter password:

Checking SELinux status...
INFO: SELinux is in permissive mode.

Checking if Percona Server is running with jemalloc enabled...
INFO: Percona Server is running with jemalloc enabled.

Checking transparent huge pages status on the system...
INFO: Transparent huge pages are currently disabled on the system.

Checking if thp-setting=never option is already set in config file...
INFO: Option thp-setting=never is not set in the config file.
      (needed only if THP is not disabled permanently on the system)

Checking TokuDB engine plugin status...
INFO: TokuDB engine plugin is not installed.

Adding thp-setting=never option into /etc/my.cnf
INFO: Successfully added thp-setting=never option into /etc/my.cnf

Installing TokuDB engine...
INFO: Successfully installed TokuDB engine plugin.

9、登录mysql
[root@linfytest3 bin]# /usr/bin/mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.6.29-76.2 Percona Server (GPL), Release 76.2, Revision ddf26fe

Copyright (c) 2009-2016 Percona LLC and/or its affiliates
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show engines;
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| Engine             | Support | Comment                                                                    | Transactions | XA   | Savepoints |
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| InnoDB             | DEFAULT | Percona-XtraDB, Supports transactions, row-level locking, and foreign keys | YES          | YES  | YES        |
| CSV                | YES     | CSV storage engine                                                         | NO           | NO   | NO         |
| MyISAM             | YES     | MyISAM storage engine                                                      | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears)             | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables                  | NO           | NO   | NO         |
| TokuDB             | YES     | Percona TokuDB Storage Engine with Fractal Tree(tm) Technology             | YES          | YES  | YES        |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                                      | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                                     | NO           | NO   | NO         |
| FEDERATED          | NO      | Federated MySQL storage engine                                             | NULL         | NULL | NULL       |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                                         | NO           | NO   | NO         |
+--------------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
10 rows in set (0.01 sec)

10、建表、索引
mysql> use test
Database changed
mysql>  CREATE TABLE timeline_1009 (
    -> uid bigint(16) unsigned not null,
    -> vflag tinyint(4) unsigned not null default 0,
    -> status_id bigint(16) unsigned not null,
    -> source int(6) unsigned not null default 0,
    -> fflag int(6) unsigned not null default 0,
    -> mflag tinyint(4) not null default 0,
    -> primary key (uid)
    -> ) engine=TokuDB DEFAULT CHARSET=utf8 ROW_FORMAT=TOKUDB_LZMA;
Query OK, 0 rows affected (0.07 sec)

mysql> create index idx_flag on timeline_1009(mflag);
Query OK, 0 rows affected (0.03 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> drop index idx_flag on timeline_1009;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> alter table timeline_1009 add column test_flag tinyint;
Query OK, 0 rows affected (0.02 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> alter table timeline_1009 drop column test_flag;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

11、

 一些注意事项
     1、alter table xxx engine=tokudb 的情况会加metadata锁阻塞插入更新, 而myql-5.6.17 innodb引擎则不会导致阻塞。     
     2、只有char, varchar, varbinary, and integer  字段类型的扩展才支持online  ddl【缩减不支持online 操作】,注意修改的时候字段属性不能发生变化,同时也不能是任何主键或二级索引的字段【二级索引的话,可以先删除二级索引,不过tokuDB创建索引二级索引并不快】,否则会导致copy表。
     3、 修改列名的时候必须是单个列修改,如果是一条语句同时修改多条语句则会copy表。
     4、这些字段TIME, ENUM, BLOB, TINYBLOB, MEDIUMBLOB, LONGBLOB类型不支持online ddl。    
     其他的一些限制详情可参考官网
 
12、tokuDB事务、锁信息查看 
      查看事务情况:
       SELECT * FROM information_schema.tokudb_trx,
        information_schema.processlist
        WHERE trx_mysql_thread_id = id; 
      
       查看锁的情况
        SELECT id FROM information_schema.tokudb_locks,
        information_schema.processlist
        WHERE locks_mysql_thread_id = id; 
      
     警告:
       不要移动任何TokuDB相关的文件、否则会导致数据库崩溃并且需要使用备份才能进行恢复。
  
(6)、 关于TokuDB行格式
    tokudb_row_format 可以设置如下的几个值:
    tokudb_default: 设置默认的压缩行为。在 TokuDB 7.1.0版本,默认使用zlib 库进行压缩,未来版本可能会改变。
    tokudb_fast: 使用quicklz 库的压缩模式。
    tokudb_small: 使用 lzma 库的压缩模式。
    tokudb_zlib: 使用 zlib 库的压缩模式,提供了中等级别的压缩比和中等级别的CPU消耗。
              
             tokudb_quicklz: 使用 quicklz 库的压缩模式, 提供了轻量级的压缩比和较低基本的CPU消耗。
             tokudb_lzma: 使用lzma库压缩模式,提供了高压缩比和高CPU消耗。
             tokudb_uncompressed: 不使用压缩模式。
    可以使用如下命令修改行格式:
     ALTER TABLE table_name ROW_FORMAT=row_format;  
     注意修改行格式的操作也是online 操作。

关于“TokuDB安装及注意事项有哪些”这篇文章就分享到这里了,希望

内容来源网络,如有侵权,联系删除,本文地址:https://www.230890.com/zhan/73744.html

(0)

相关推荐

  • javascript中如何监听页面DOM变动并高效响应

    技术javascript中如何监听页面DOM变动并高效响应本篇内容介绍了“javascript中如何监听页面DOM变动并高效响应”的有关知识,在实际案例的操作过程中,不少人都会遇到这样的困境,接下来就让小编带领大家学习一

    攻略 2021年11月15日
  • 正确写SQL的方法有哪些

    技术正确写SQL的方法有哪些这篇文章主要介绍“正确写SQL的方法有哪些”,在日常操作中,相信很多人在正确写SQL的方法有哪些问题上存在疑惑,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”正确写SQL的方法

    攻略 2021年10月23日
  • 猪宝宝小名,你孩子的名字是自己起的吗

    技术猪宝宝小名,你孩子的名字是自己起的吗是的,把我和孩子带坑里去了猪宝宝小名。尤其是我女儿的。生产前并不知道性别,所以就没先给孩子取名,出生后也才被告知要3天内取名,所以当时挺急的,女儿又是双方家庭的第一个孩子。此为背景

    生活 2021年10月30日
  • MySQL中pt-duplicate-key-checker工具怎么用

    技术MySQL中pt-duplicate-key-checker工具怎么用这篇文章主要为大家展示了“MySQL中pt-duplicate-key-checker工具怎么用”,内容简而易懂,条理清晰,希望能够帮助大家解决疑

    攻略 2021年11月2日
  • C++使用标准概念有什么优点

    技术C++使用标准概念有什么优点本篇内容主要讲解“C++使用标准概念有什么优点”,感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷,实用性强。下面就让小编来带大家学习“C++使用标准概念有什么优点”吧!T.11:只要可

    攻略 2021年11月24日
  • python预计运行时间怎么做(python对时间和日期的处理)

    技术python如何对日期时间进行处理这篇文章给大家分享的是有关python如何对日期时间进行处理的内容。小编觉得挺实用的,因此分享给大家做个参考,一起跟随小编过来看看吧。开发中常用的日期操作有哪些?获取当前时间获取系统

    攻略 2021年12月19日