How to use subquery to define Mysql SELECT LIMIT offset?

Question

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

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

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

Avoid the pain, do two queries mate, even if you succeed IMHO you'r code will be much messier. That's just my opinion :) — DivinesLight
– DivinesLight, Commented Nov 18, 2011 at 11:35
Looks like duplicate How to make limit offset dynamic using only (My)SQL — Michał Powaga
– Michał Powaga, Commented Nov 18, 2011 at 11:36

Nemoden · Accepted Answer · 2014-09-04 02:46:37Z

2

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

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

answered Nov 18, 2011 at 11:36

Nemoden

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Comments

Community · Accepted Answer · 2017-05-23 11:47:59Z

0

Basically if you're not in a stored procedure or a prepared statement you can't do it.

If you have a stored procedure just assign a variable the value of your "inner" select and use that on the real statement.

If you have a prepared statement use "limit ?, ?" and set the values from the call.

CommunityBot

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answered Nov 18, 2011 at 11:45

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