数据库|mysql教程
mysql,存储,动态
数据库-mysql教程
–删除
drop procedure if exists up_common_select
–创建
CREATEPROCEDURE `up_common_select`
(
in t_name varchar(50)
)
begin
declare v_sql varchar(500);
set v_sql= concat(‘select * from ‘,t_name);
select v_sql;
–注意:prepare(预处理)execute stmt using @var,只能跟@var变量,declare和传入的变量不行!!!
set @v_sql=v_sql;
prepare stmt from @v_sql;
EXECUTE stmt ;
deallocate prepare stmt;
end;
–调用
call up_common_select(‘admin_authority’);
注意事项
1mysql5.0.13之后支持在存储过程中调用prepare
2prepare stmt from ‘select * from ?’;(错)
mysql5.0.24,prepare尚不支持 表名做变量!
解决方案:用 contat()函数,组合字符串
3execute stmt [using @var,@var2]
必须是@var形式的变量,传入的参数变量,declare变量不行
4.deallocate prepare stmt; 显式的释放prepare,如果不释放,mysql会释放,!
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