Use LIMIT to paginate results in MySQL query

问题:

I want to fetch my results a 'page' at a time; I want the page number to be a parameter (in a JDBC prepared statement). Consider the following snippet

SELECT * FROM thread t ORDER BY t.id LIMIT ((? - 1) * 20), 20

So ideally, this would result, for page 1, to LIMIT 0, 20.

When I test

SELECT * FROM thread t ORDER BY t.id LIMIT ((1 - 1) * 20), 20

I am told I have a syntax error. I don't see what it could be, though - it's just some simple math. All it tells me is

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '((1 - 1) * 20), 20' at line 1

What am I doing wrong with my LIMIT clause, and how can I fix it?

回答1:

MySQL requires numeric constants for that LIMIT syntax.

From http://dev.mysql.com/doc/refman/5.7/en/select.html:

The LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants, with these exceptions:

• Within prepared statements, LIMIT parameters can be specified using ? placeholder markers.

• Within stored programs, LIMIT parameters can be specified using integer-valued routine parameters or local variables.

Compute the constant on the Java side.

回答2:

This cannot be done.

See solution here: MySQL Math and COUNT(*) in LIMIT

I would recommend using javascript or something to handle the first parameter (i.e. offset) such as: limit 0,20 on first page and limit 21,20 on second...

For example if your first page has a get variable in the url www.example.com?page=1

offset = (page - 1)*20 ;
row_count = 20;
select * from table limit (offset, row_count);

回答3:

Define Offset for the query.

For example

if you want page-1 (records 1-10) offset=0,limit=10; for page-2 (records 11-20) offset =20,limit =10; and use the following query :

SELECT column FROM table LIMIT {someLimit} OFFSET {someOffset};

example:

SELECT column FROM table
LIMIT 10 OFFSET 10;