Mysql存储过程查询结果赋值到变量的方法

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Mysql存储过程查询结果赋值到变量的方法_MySQL

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Jun 01, 2016 pm 01:30 PM

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Mysql存储过程查询结果赋值到变量的方法

把查询结果赋值到变量，大部分情况下使用游标来完成，但是如果明确知道查询结果只有一行（例如统计记录的数量，某个字段求和等），其实可以使用set或into的方式来实现赋值。示例代码：

01drop table if exists test_tbl;02create table test_tbl (name varchar(20), status int(2));03insert into test_tbl values(&#39;abc&#39;, 1),(&#39;edf&#39;, 2),(&#39;xyz&#39;, 3);0405drop procedure IF EXISTS pro_test_3;06delimiter //07create procedure pro_test_3()08begin09--  方式 110    DECLARE cnt INT DEFAULT 0;11    select count(*) into cnt from test_tbl;12    select cnt;1314--  方式 215    set @cnt = (select count(*) from test_tbl);16    select @cnt;1718--  方式 319    select count(*) into @cnt1 from test_tbl;20    select @cnt1;2122--  多个列的情况下似乎只能用 into 方式23    select max(status), avg(status) into @max, @avg from test_tbl;24    select @max, @avg;25end26//27delimiter ;2829call pro_test_3();

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