从LEFT JOIN的表格中仅选择一些列 [英] Select only some columns from a table on a LEFT JOIN

问题描述

是否可以从LEFT JOIN的表中仅选择某些列?

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

推荐答案

当然可以.只需列出要在任何查询中选择的列即可:

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，我在所有列上都添加了table1.或table2.前缀，以确保两个表中都存在具有相同名称的字段时没有歧义.

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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