仅从左联接的表中选择一些列

2021-12-17 00:00:00 join mysql

是否可以在 LEFT JOIN 的表中只选择一些列?

Is it possible to select only some columns from a table on a LEFT JOIN?

推荐答案

当然.只需像在任何查询中一样列出您要选择的列:

Of course. Just list the columns you want to select as you would in any query:

SELECT table1.column1, table1.column2, table2.column3
FROM table1
LEFT JOIN table2 ON (...)

请注意,我在所有列中都包含了 table1.table2. 前缀,以确保在其中存在同名字段时不会出现任何歧义两个表.

Note that I've included the table1. or table2. prefix on all columns to be sure there aren't any ambiguities where fields with the same name exist in both tables.

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