mysql 游标中的记录数没有迭代? [英] mysql number of records in cursor without iterating?

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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