如何使用子查询定义Mysql SELECT LIMIT偏移量? [英] How to use subquery to define Mysql SELECT LIMIT offset?

问题描述

我一直在尝试动态"定义查询的偏移量.

I have been trying to define "dynamically" the offset of a query.

但是执行此查询时，我总是以You have an error in your SQL syntax;

But when executing this query I always end up with a You have an error in your SQL syntax;

当我用数字替换子查询时，它确实可以正常工作.具有这种形状的查询中有问题吗?

When I do remplace the subquery by a number it does work fine. Is there something wrong in a query that has this shape?

SELECT LengthOfStay
FROM table1
LIMIT (SELECT CAST(COUNT(DISTINCT(LengthOfStay)) / 2 AS SIGNED) FROM table1 t1), 2;

Ps.我对其进行了强制转换，以确保它是整数.

Ps. I casted it so I can make sure it's an integer.

推荐答案

不能将子查询用作LIMIT参数.限制参数应为INTEGER.基本上，您的子查询返回了一个表.

You can not use a subquery as a LIMIT argument. Limit argument should be an INTEGER. Your subquery returns, well... basically, a table.

无论如何，此查询试图实现什么?这个查询对我来说没有任何意义...

What are trying to achieve by this query anyway? This query does not make any sense to me...

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