postgresql 如果选择查询中的条件

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时间:2020-09-10 22:56:50  来源:igfitidea点击:

If condition in select query

postgresql

提问by Rafiu

select email from mailing list

This is the query i want to use ifcondition. I have a column in mailing list as unsub. If this unsubis truethe email should null in the selected result otherwise the email will be the selected result

这是我想使用if条件的查询。我在邮件列表中有一个列作为unsub. 如果这unsubtrue电子邮件在所选结果中应为空,否则电子邮件将是所选结果

回答by davek

select case unsub when true then null else email end as email,....
from ...

see the docs for more examples.

有关更多示例,请参阅文档