select * from zyj_dxzxyh where name in (select name from zyj_dxzxyh group by name having count(name) > 1) # 查找表中多余的重复记录 # 选择 * 所有列 从表zyj_dxzxyh  # where 条件过滤  name 列 是字句 # 字句：选择name列   group by 分

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create [or replace] procedure 存储过程名（param1 in type，param2 out type）as   变量1 类型（值范围）;   变量2 类型（值范围）;begin   select count(*) into 变量1 from 表A where列名=param1；   if (判断条件) then        select 列名 into

<?php$dbhost = 'localhost';  // mysql服务器主机地址$dbuser = 'root';            // mysql用户名$dbpass = '123456';          // mysql用户名密码$conn = mysqli_connect($dbhost, $dbuser, $dbpass);if(! $co