[Mysql 语法学习] Mysql多种sql语法图解

快来打我* 2023-10-04 08:46 3阅读 0赞

### 图形学习笔记: ###

内连接:  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70]  
左连接:

![在这里插入图片描述][20210320100404915.png]

右连接:

![在这里插入图片描述][20210320100430622.png]

左条件连接 +条件:  
![在这里插入图片描述][20210320100500327.png]

右连接 +条件  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 1]

--------------------

全连接,和全连接+条件  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 2]

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 3]  
**交叉连接 cross join**  
![在这里插入图片描述][20210319193841681.png]

**等值连接**  
下面二个语句效果完全一样 不同的原因是根据 92 / 99语法来变化的

查询对应二个关联表的表数据
    
    
    SELECT  列名,....
    FROM 表名1,表名2 
    WHERE 表名1.外键表名2的id = 表名2.id
    
    SELECT  列名,....
    FROM 表名1 INNER JOIN 表名2
    ON 表名1.外键表名2的id = 表名2.id

查询  name包含e的  列名数据  (筛选)
    
    SELECT  列名,....
    FROM 表名1 INNER JOIN 表名2
    ON 表名1.外键表名2的id = 表名2.id
    WHERE  表名1.name LIKE '%e%'

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 4]

--------------------

**外连接**  
![在这里插入图片描述][20210320100032574.png]

![在这里插入图片描述][20210320095623298.png]

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 5]

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[20210320100404915.png]: https://img-blog.csdnimg.cn/20210320100404915.png
[20210320100430622.png]: https://img-blog.csdnimg.cn/20210320100430622.png
[20210320100500327.png]: https://img-blog.csdnimg.cn/20210320100500327.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/2021032010051749.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20210320100640669.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 3]: https://img-blog.csdnimg.cn/20210319193612513.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU,size_16,color_FFFFFF,t_70
[20210319193841681.png]: https://img-blog.csdnimg.cn/20210319193841681.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 4]: https://img-blog.csdnimg.cn/20210319195452897.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU,size_16,color_FFFFFF,t_70
[20210320100032574.png]: https://img-blog.csdnimg.cn/20210320100032574.png
[20210320095623298.png]: https://img-blog.csdnimg.cn/20210320095623298.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU_size_16_color_FFFFFF_t_70 5]: https://img-blog.csdnimg.cn/20210320094010413.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NxTDUyMGxU,size_16,color_FFFFFF,t_70