MySQL :: MySQL 8.4 Reference Manual :: 15.2.13.2 JOIN Clause https://dev.mysql.com/doc/refman/8.4/en/join.html MySQL LEFT JOIN Keyword https://www.w3s
一、sql的left join 、right join 、inner join之间的区别 left join(左联接) 返回包括左表中的所有记录和右表中联结字段相等的记录 right join...(右联接) 返回包括右表中的所有记录和左表中联结字段相等的记录 inner join(等值连接) 只返回两个表中联结字段相等的行 outer join(外连接) 可分为左外连接...
ExampleGet your own SQL Server Join Products and Categories with the INNER JOIN keyword: SELECTProductID, ProductName, CategoryName FROMProducts INNERJOINCategoriesONProducts.CategoryID = Categories.CategoryID; Try it Yourself » Note:TheINNER JOINkeyword returns only rows with a match in both table...