SQL基础笔记（3）- DBMS数据库管理系统相关查询语句

迈不过友情╰ 2023-06-19 09:50 1阅读 0赞

### SQL基础笔记（3）- DBMS相关查询语句 ###

*  1. 开启SQL语句执行时间
 *   *  1.1 查询\`profiling\`
     *  1.2 设置\`profiling\`
 *  2. SQL执行历史查询
 *   *  2.1 执行历史
     *  2.2 执行过程的具体时间
 *  3. 查看DBMS MySQL的版本

# 1. 开启SQL语句执行时间 #

如何知道 SQL 执行时所使用的资源情况，开启`profiling`

## 1.1 查询`profiling` ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70]

mysql> select @@profiling;

## 1.2 设置`profiling` ##

mysql> set profiling=1;

# 2. SQL执行历史查询 #

## 2.1 执行历史 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 1]

mysql> show profiles;

## 2.2 执行过程的具体时间 ##

mysql> show profile for query 4;

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 2]

# 3. 查看DBMS MySQL的版本 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 3]

mysql> select version();

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20191205175106381.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20191205175735693.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20191205175818946.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4_size_16_color_FFFFFF_t_70 3]: https://img-blog.csdnimg.cn/20191205175922163.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2FhMzkwNDgxOTc4,size_16,color_FFFFFF,t_70