SELECT TABLE_SCHEMA,TABLE_NAME FROM information_schema.`COLUMNS`
WHERE COLUMN_NAME='字段名'
查找字段在数据库中的那个表 mysql
use information_schema;
select * from columns where column_name='字段名' ;
查找表字段和其注释
SELECT COLUMN_NAME,column_comment FROM INFORMATION_SCHEMA.Columns WHERE table_name='表名'
//查看字段重复
select order_id,count(*) as count from表名 group by order_id having count>1;