zoukankan      html  css  js  c++  java
  • sql查询

    创建数据库
    create database database-name;

    删除数据库
    drop database dbname;
    

    增加一个列:

    alter table tablename add column columnname type;

    创建视图:

    create view viewname as select statement;

    删除视图:

    drop view viewname;

    复制表:

    select * into b from a where 1<>1(仅用于SQlServer)

    常用:

    • 选择:select * from table1 where 范围
    • 插入:insert into table1(field1,field2) value(value1,value2);
    • 更新:update table1 set field1=value1 where 范围
    • 查找:select * from table1 where field1 like ‘%value%’               –like语句的模糊查询
    • 排序:select * from table1 order by field1,field [desc/asc]
    • 总数:select count(*) as tatolcount from table1
    • 求和:select sum(field1) as sumvalue from table1
    • 最大:select max(field1) as maxvalue from table1
    • 最小:select min(field1) as minvalue from table1

    修改数据库名称: sp_renamedb 'old_name','new_name';

    子查询:select a,b,c from a where a IN(select d from b)

    between和not between 的用法:select * from table1 where time between time1 and time2-----------select  a,b,c from table1 where a not between 数值1 and 数值2

    找出所有的表:select name from sysobjects where type='U' //U代表用户

    表的所有列名:select name from syscolumns where id=object_id('tablename');

    分离数据库:sp_detach_db;


    附加数据库:sp_attach_db 后接表名(附加需要完整的路径名)

    技巧:

    "where 1=1" 是表示选择全部,“where 1=2”全部不选

    按笔画数排序:select * from TableName Order by by CustomerName Collate Chinese_PRC_Stroke_ci_as //从少到多

    查看当前数据库中所有存储过程:select dbid, name AS DB_NAME from master..sysdatabases where sid <> 0x01

    查询一个表的字段和数据类型:select column_name,data_type from information_schema.columns where table_name='表名'

    转自:https://blog.csdn.net/hundan_520520/article/details/53580289

  • 相关阅读:
    01前端-html
    2-3程序流程
    2-2视频缓存池
    2-1图像像素格式深度理解
    3.1.1 文件系统介绍
    3.1.4 文件属性
    CentOS开放端口的方法
    宝塔linux面板命令大全
    如何卸载Win10 RS3上预装的office2016
    win10家庭版升级专业版的两种方法和密钥
  • 原文地址:https://www.cnblogs.com/Renzhendew0/p/9674279.html
Copyright © 2011-2022 走看看