Doraemon_meow_meow的博客

建立数据库时可以使用以下命令：create database hys character set utf8; 修改数据库编码的命令为：alter database app_relation character set utf8;

数据导出-- 将lamp138库导出D:\>mysqldump -u root -p lamp138 >D:/lamp138.sqlEnter password:---- 将lamp138库中的stu表导出D:\>mysqldump -u root -p lamp138 stu >D:/>lamp138_stu.sqlEnter password:数据...

正常写语句顺序select , form where ,group by , having ,order by ,limit 执行顺序from， where ， group by , select , having , order by ,limit

mysql的条件判断SELECT`产品号码`,`产品名称`,`产品单价`,CASEWHEN `产品单价`<(SELECT AVG(`产品单价`) FROM `产品信息`) THEN 1WHEN `产品单价`>=2*(SELECT AVG(`产品单价`) FROM `产品信息`) THEN 2ELSE 3END AS `顾客级别`FROM `产品信息`;mysq...

ERROR 1366 (HY000): Incorrect string value: ‘\xE8\xB5\xB5\xE9\x9B\xB7’ for column ‘Sname’ at row 1错误描述我的操作步骤：1、创建数据库test，语句：create database test;2、创建Student表：create table Student(SId varchar(10)...