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MySql学习之Join查询

本文章为尚硅谷教学视频总结,仅供学习及参考。如有侵权请及时告知。

1、SQL执行顺序

(1)手写sql顺序

(2)机读sql顺序

2、7种Join的sql编写

注:图中 full outer join在MySQL中是不支持的。可通过

(1)全有

SELECT <select_list> FROM TableA A LEFT JOIN TableB B ON A.Key = B.KeyUNIONSELECT <select_list> FROM TableA A RIGHT JOIN TableB B ON A.Key = B.Key123123

(2)A的独有和B的独有

SELECT <select_list> FROM TableA A LEFT JOIN TableB B ON A.Key = B.Key WHERE B.Key IS NULLUNIONSELECT <select_list> FROM TableA A RIGHT JOIN TableB B ON A.Key = B.Key WHERE A.Key IS NULL

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