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android 安卓SQL语句大全

基础创建数据库创建之前判断该数据库是否存在if exists (select * from sysdatabases where name='databaseName')drop database databaseNamegoCreate DATABASE database-name删除数据库drop......

基础

创建数据库

创建之前判断该数据库是否存在

if exists (select * from sysdatabases where name='databaseName')

drop database databaseName

go

Create DATABASE database-name

删除数据库

drop database dbname

备份sql server

--- 创建 备份数据的 device

USE master

EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'

--- 开始 备份

BACKUP DATABASE pubs TO testBack

创建新表

create table tabname(col1 type1 [not null] [primary key],col2 type2 [not null],)

根据已有的表创建新表:

A:go

use 原数据库名

go

select * into 目的数据库名.dbo.目的表名 from 原表名(使用旧表创建新表)

B:create table tab_new as select col1,col2… from tab_old definition only

创建序列

create sequence SIMON_SEQUENCE

minvalue 1 -- 最小值

maxvalue 999999999999999999999999999 最大值

start with 1 开始值

increment by 1 每次加几

cache 20;

删除新表

drop table tabname

增加一个列

Alter table tabname add column col type

注:列增加后将不能删除.DB2中列加上后数据类型也不能改变,唯一能改变的是增加varchar类型的长度.

添加主键

Alter table tabname add primary key(col)

说明:删除主键: Alter table tabname drop primary key(col)

创建索引

create [unique] index idxname on tabname(col….)

删除索引:drop index idxname on tabname

注:索引是不可更改的,想更改必须删除重新建.

创建视图

create view viewname as select statement

删除视图:drop view viewname

几个简单的基本的sql语句

选择:select * from table1 where 范围

插入:insert into table1(field1,field2) values(value1,value2)

删除:delete from table1 where 范围

更新:update table1 set field1=value1 where 范围

查找:select * from table1 where field1 like ’%value1%’ (所有包含‘value1’这个模式的字符串)---like的语法很精妙,查资料!

排序:select * from table1 order by field1,field2 [desc]

总数:select count(*) as totalcount from table1

求和:select sum(field1) as sumvalue from table1

平均:select avg(field1) as avgvalue from table1

最大:select max(field1) as maxvalue from table1

最小:select min(field1) as minvalue from table1[separator]

几个高级查询运算词

A: UNION 运算符

UNION 运算符通过组合其他两个结果表(例如 TABLE1 和 TABLE2)并消去表中任何重复行而派生出一个结果表.当 ALL 随 UNION 一起使用时(即 UNION ALL),不消除重复行.两种情况下,派生表的每一行不是来自 TABLE1 就是来自 TABLE2.

B: EXCEPT 运算符

EXCEPT 运算符通过包括所有在 TABLE1 中但不在 TABLE2 中的行并消除所有重复行而派生出一个结果表.当 ALL 随 EXCEPT 一起使用时 (EXCEPT ALL),不消除重复行.

C: INTERSECT 运算符

INTERSECT 运算符通过只包括 TABLE1 和 TABLE2 中都有的行并消除所有重复行而派生出一个结果表.当 ALL 随 INTERSECT 一起使用时 (INTERSECT ALL),不消除重复行.

注:使用运算词的几个查询结果行必须是一致的.

使用外连接

A、left outer join:

左外连接(左连接):结果集既包括连接表的匹配行,也包括左连接表的所有行.

SQL: select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c

B:right outer join:

右外连接(右连接):结果集既包括连接表的匹配连接行,也包括右连接表的所有行.

C:full outer join:

全外连接:不仅包括符号连接表的匹配行,还包括两个连接表中的所有记录.

编辑本段

判断对象是否存在

判断数据库是否存在

if exists (select * from sys.databases where name = '数据库名')

drop database [数据库名]

判断表是否存在

if not exists (select * from sysobjects where [name] = '表名' and xtype='U')

begin

--这里创建表

end

判断存储过程是否存在

if exists (select * from sysobjects where id = object_id(N'[存储过程名]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)

drop procedure [存储过程名]

判断临时表是否存在

if object_id('tempdb#临时表名') is not null

drop table #临时表名

判断视图是否存在

--SQL Server 2000

IF EXISTS (SELECT * FROM sysviews WHERE object_id = '[dbo].[视图名]'

--SQL Server 2005

IF EXISTS (SELECT * FROM sys.views WHERE object_id = '[dbo].[视图名]'

判断函数是否存在

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[函数名]') and xtype in (N'FN', N'IF', N'TF'))

drop function [dbo].[函数名]

获取用户创建的对象信息

SELECT [name],[id],crdate FROM sysobjects where xtype='U'

/*

xtype 的表示参数类型,通常包括如下这些 C = CHECK 约束 D = 默认值或 DEFAULT 约束 F = FOREIGN KEY 约束 L = 日志 FN = 标量函数 IF = 内嵌表函数 P = 存储过程 PK = PRIMARY KEY 约束(类型是 K) RF = 复制筛选存储过程 S = 系统表 TF = 表函数 TR = 触发器 U = 用户表 UQ = UNIQUE 约束(类型是 K) V = 视图 X = 扩展存储过程 */

判断列是否存在

if exists(select * from syscolumns where id=object_id('表名') and name='列名')

alter table 表名 drop column 列名

判断列是否自增列

if columnproperty(object_id('table'),'col','IsIdentity')=1

print '自增列'

else

print '不是自增列'

SELECT * FROM sys.columns WHERE object_id=OBJECT_ID('表名')

AND is_identity=1

判断表中是否存在索引

if exists(select * from sysindexes where id=object_id('表名') and name='索引名')

print '存在'

else

print '不存在

查看数据库中对象

SELECT * FROM sys.sysobjects WHERE name='对象名'

编辑本段

提升

复制表

(只复制结构,源表名:a 新表名:b) (Access可用)

法一:select * into b from a where 1<>1

法二:select top 0 * into b from a

拷贝表

(拷贝数据,源表名:a 目标表名:b) (Access可用)

insert into b(a, b, c) select d,e,f from b;

跨数据库之间表的拷贝

(具体数据使用绝对路径) (Access可用)

insert into b(a, b, c) select d,e,f from b in ‘具体数据库’ where 条件

例子:from b in '"&Server.MapPath("."&"\data.mdb" &"' where

子查询

(表名1:a 表名2:b)

select a,b,c from a where a IN (select d from b 或者: select a,b,c from a where a IN (1,2,3)

显示文章、提交人和最后回复时间

select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b

外连接查询

(表名1:a 表名2:b)

select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c

在线视图查询

(表名1:a

select * from (Select a,b,c FROM a) T where t.a > 1;

between的用法

between限制查询数据范围时包括了边界值,not between不包括

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

in 的使用方法

select * from table1 where a [not] in (‘值1’,’值2’,’值4’,’值6’)

删除主表中已经在副表中没有的信息

两张关联表delete from table1 where not exists ( select * from table2 where table1.field1=table2.field1

四表联查问题

select * from a left inner join b on a.a=b.b right inner join c on a.a=c.c inner join d on a.a=d.d where …

日程安排提前五分钟提醒

SQL: select * from 日程安排 where datediff('minute',f开始时间,getdate())>5

一条sql 语句搞定数据库分页

select top 10 b.* from (select top 20 主键字段,排序字段 from 表名 order by 排序字段 desc) a,表名 b where b.主键字段 = a.主键字段 order by a.排序字段

前10条记录

select top 10 * form table1 where 范围

选择排名

选择在每一组b值相同的数据中对应的a最大的记录的所有信息(类似这样的用法可以用于论坛每月排行榜,每月热销产品分析,按科目成绩排名,等等.)

select a,b,c from tablename ta where a=(select max(a) from tablename tb where tb.b=ta.b)

派生结果表

包括所有在 TableA 中但不在 TableB和TableC 中的行并消除所有重复行而派生出一个结果表

(select a from tableA except (select a from tableB) except (select a from tableC)

随机取出10条数据

select top 10 * from tablename order by newid()

随机选择记录

select newid()

删除重复记录

Delete from tablename where id not in (select max(id) from tablename group by col1,col2,…)

列出数据库里所有的表名

select name from sysobjects where type='U'

列出表里的所有的

select name from syscolumns where id=object_id('TableName')

列示排列

列示type、vender、pcs字段,以type字段排列,case可以方便地实现多重选择,类似select 中的case.

select type,sum(case vender when 'A' then pcs else 0 end),sum(case vender when 'C' then pcs else 0 end),sum(case vender when 'B' then pcs else 0 end) FROM tablename group by type

显示结果:

type vender pcs

电脑 A 1

电脑 A 1

光盘 B 2

光盘 A 2

手机 B 3

手机 C 3

初始化表table1

TRUNCATE TABLE table1

选择从10到15的记录

select top 5 * from (select top 15 * from table order by id asc) table_别名 order by id desc

数据类型转换

declare @numid int

declare @id varchar(50)

set @numid=2005

set @id=convert(varchar,@numid)

通过上述语句完成数据类型Int转换成varchar,其他转换类似,可参看convert函数

编辑本段

技巧

1=1,1=2的使用

在SQL语句组合时用的较多

“where 1=1” 是表示选择全部 “where 1=2”全部不选,

如:

if @strWhere !='

begin

set @strSQL = 'select count(*) as Total from [' + @tblName + '] where ' + @strWhere

end

else

begin

set @strSQL = 'select count(*) as Total from [' + @tblName + ']'

end

我们可以直接写成

set @strSQL = 'select count(*) as Total from [' + @tblName + '] where 1=1 and '+ @strWhere

收缩数据库

--重建索引

DBCC REINDEX

DBCC INDEXDEFRAG

--收缩数据和日志

DBCC SHRINKDB

DBCC SHRINKFILE

压缩数据库

dbcc shrinkdatabase(dbname)

转移数据库给新用户以已存在用户权限

exec sp_change_users_login 'update_one','newname','oldname'

go

检查备份集

RESTORE VERIFYONLY from disk='E:\dvbbs.bak'

修复数据库

Alter DATABASE [dvbbs] SET SINGLE_USER

GO

DBCC CHECKDB('dvbbs',repair_allow_data_loss) WITH TABLOCK

GO

Alter DATABASE [dvbbs] SET MULTI_USER

GO

日志清除

SET NOCOUNT ON

DECLARE @LogicalFileName sysname,

@MaxMinutes INT,

@NewSize INT

USE tablename -- 要操作的数据库名

Select @LogicalFileName = 'tablename_log', -- 日志文件名

@MaxMinutes = 10, -- Limit on time allowed to wrap log.

@NewSize = 1 -- 你想设定的日志文件的大小(M)

-- Setup / initialize

DECLARE @OriginalSize int

Select @OriginalSize = size

FROM sysfiles

Where name = @LogicalFileName

Select 'Original Size of ' + db_name() + ' LOG is ' +

CONVERT(VARCHAR(30),@OriginalSize) + ' 8K pages or ' +

CONVERT(VARCHAR(30),(@OriginalSize*8/1024)) + 'MB'

FROM sysfiles

Where name = @LogicalFileName

Create TABLE DummyTrans

(DummyColumn char (8000) not null)

DECLARE @Counter INT,

@StartTime DATETIME,

@TruncLog VARCHAR(255)

Select @StartTime = GETDATE(),

@TruncLog = 'BACKUP LOG ' + db_name() + ' WITH TRUNCATE_ONLY'

DBCC SHRINKFILE (@LogicalFileName, @NewSize)

EXEC (@TruncLog)

-- Wrap the log if necessary.

WHILE @MaxMinutes > DATEDIFF (mi, @StartTime, GETDATE()) -- time has not expired

AND @OriginalSize = (Select size FROM sysfiles Where name = @LogicalFileName)

AND (@OriginalSize * 8 /1024) > @NewSize

BEGIN -- Outer loop.

Select @Counter = 0

WHILE ((@Counter < @OriginalSize / 16) AND (@Counter < 50000))

BEGIN -- update

Insert DummyTrans VALUES ('Fill Log')

Delete DummyTrans

Select @Counter = @Counter + 1

END

EXEC (@TruncLog)

END

Select 'Final Size of ' + db_name() + ' LOG is ' +

CONVERT(VARCHAR(30),size) + ' 8K pages or ' +

CONVERT(VARCHAR(30),(size*8/1024)) + 'MB'

FROM sysfiles

Where name = @LogicalFileName

Drop TABLE DummyTrans

SET NOCOUNT OFF

更改某个表

exec sp_changeobjectowner 'tablename','dbo'

存储更改全部表

Create PROCEDURE dbo.User_ChangeObjectOwnerBatch

@OldOwner as NVARCHAR(128),

@NewOwner as NVARCHAR(128)

AS

DECLARE @Name as NVARCHAR(128)

DECLARE @Owner as NVARCHAR(128)

DECLARE @OwnerName as NVARCHAR(128)

DECLARE curObject CURSOR FOR

select 'Name' = name,

'Owner' = user_name(uid)

from sysobjects

where user_name(uid) =@OldOwner

order by name

OPEN curObject

FETCH NEXT FROM curObject INTO @Name, @Owner

WHILE(@@FETCH_STATUS=0)

BEGIN

if @Owner=@OldOwner

begin

set @OwnerName = @OldOwner + '.' + rtrim(@Name)

exec sp_changeobjectowner @OwnerName, @NewOwner

end

-- select @name,@NewOwner,@OldOwner

FETCH NEXT FROM curObject INTO @Name, @Owner

END

close curObject

deallocate curObject

GO

SQL SERVER中直接循环写入数据

declare @i int

set @i=1

while @i<30

begin

insert into test (userid) values(@i)

set @i=@i+1

end