left outer join 3个表

left outer join 用于将左侧表中的所有行与右侧表中满足连接条件的行进行连接，并且如果右侧表中没有匹配的行，则会返回空值。在这种连接中，左侧表中的所有行都会被包含在结果集中，而右侧表中没有匹配的行则会用空值填充。<em>1</em><em>2</em><em>3</em>
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- *1* *3* [left join和left outer join 有什么区别？这样解释通俗易懂](https://blog.csdn.net/X8i0Bev/article/details/125025550)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v92^chatsearchT0_1"}} ] [.reference_item]
- *2* [mySQL SELECT Left Outer Join涉及2个以上的表(mySQL SELECT Left Outer Join involving more than 2 ...](https://blog.csdn.net/weixin_39736606/article/details/114329707)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v92^chatsearchT0_1"}} ] [.reference_item]
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