left join同名字段
时间: 2023-10-11 17:05:51 浏览: 75
在left join中,如果左表和右表有同名字段,那么查询结果中会保留两个同名字段,一个来自左表,一个来自右表。可以通过指定表别名来区分这两个同名字段。例如,如果左表的同名字段为A,右表的同名字段为B,那么查询结果中会出现A和B两个字段。你可以使用表别名来引用这些字段,例如左表的同名字段可以使用"表别名.A"来引用,右表的同名字段可以使用"表别名.B"来引用。<span class="em">1</span><span class="em">2</span><span class="em">3</span>
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