本文介绍了mysql 游标中的记录数没有迭代?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我正在尝试为以下逻辑编写 mysql 程序,
I am trying to write mysql procedure for below logic,
select id, fullname from users where fullname like concat(lastname, ' ', firstname, ' (' , middlename, '%');
如果上面的查询返回0条记录则
if above query returns 0 records then
select id, fullname from users where fullname like concat(lastname, ' ', firstname, '%');
.... few more queries depending upon result,
我正在尝试编写程序 mysql 程序,其中,我使用的是 mysql 游标,
I am trying to write procedure mysql procedure , in that, I am using mysql cursor,
DECLARE user_cnt CURSOR FOR select id, fullname from users where fullname like concat(lastname, ' ', firstname, ' (' , middlename, '%');
现在我想检查 user_cursor 中的记录数,以便我可以检查条件如果查询返回 0 条记录"
now I want to check number of records in user_cursor so that I can check the condition "if query returns 0 records then"
如何在不迭代的情况下找到mysql游标中的记录数?
How can I find the number of records in mysql cursor without iterating on it ?
推荐答案
在光标前计数:
select count(*)
into @user_cnt
from users
where fullname like concat (
lastname,
' ',
firstname,
' (',
middlename,
'%'
);
如果你想在 OPENING 游标之后再做,试试做:
If you want to do it after OPENING the cursor, try doing:
OPEN your_cursor;
select FOUND_ROWS() into user_cnt ;
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