没有条件时，如何使查询不返回任何内容? [英] How do I make a query return nothing when there are no conditions?

问题描述

相当简单，我有一对多/多对一的关系，我想查询一下.但是，当WHERE子句信息未提供时，我不希望返回任何结果.

Rather simple, I have a one to many / many to one relation and I'd like to query it. However, I don't want any results returned when it isn't provided with any WHERE clause information.

简单来说，如何使查询变得非贪婪?

In simpler terms, how do I make a query non-greedy?

推荐答案

您可以添加一个始终为false的where子句，并附加您希望随OR提供的条件:

You could add a where clause that is always false and append the condition you want supplied with OR:

select * from table where 1 = 0 OR (real conditions)

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