dongmaijie5200 2018-01-28 20:58
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MySQL左外连接问题双重id [重复]

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I'm using a left outer join in a query. but now I'm getting a double id, What I mean is that I now get the id of table 1 and the id of table2 both called id.

Is there a way to maybe rename(prefix) the id of table 2 with something like table2_id? without having to use 'AS table_nameOfColumn' for every column of table 2

My current query:

SELECT invoices.*, clients.* FROM invoices 
LEFT OUTER JOIN users ON invoices.employee_id = users.id 
LEFT OUTER JOIN clients ON users.client_id = clients.id
WHERE invoices.employee_id = 3
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  • douw92892 2018-01-28 21:06
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    you can simply add an alias to your columns name naming explicitally

    eg:

      SELECT invoices.id as invoce_id, clients.id as client_id FROM invoices 
      LEFT OUTER JOIN users ON invoices.employee_id = users.id 
      LEFT OUTER JOIN clients ON users.client_id = clients.id
      WHERE invoices.employee_id = 3
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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