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修改限制和偏移的Mysql过程
原标题:Mysql procedure to modify limit and offset

这只是我的想法,但是否不可能在MySQL中创建一个函数来修改查询中的<code>LIMIT</code>

该子句将是一个简单的计算函数,它将根据每页的pageno*计算偏移量

实例

SELECT * FROM items PAGE(4,20)

这与

SELECT * FROM items LIMIT 100,20

我以前从未创建过任何程序,所以下面的内容是错误的。。

CREATE PROCEDURE (int pagno, int limit)
BEGIN
     ofsset = roundup(pageno * limit)
END

但在该查询中,是否真的设置了查询的限制和偏移量?

问题回答

你可以这样做:

drop procedure if exists foo;

delimiter #

create procedure foo
(
in p_limit int unsigned
)
proc_main:begin

set SQL_SELECT_LIMIT = p_limit;

select * from <table>...

set SQL_SELECT_LIMIT = DEFAULT; 

end proc_main #

delimiter ;
call foo(64);




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