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常用精粹SQL语句大全,Sql的基础知识本领

2019-09-16 作者:数据库网络   |   浏览(168)

三、技巧
1、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

三、技巧

1、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

错误!未找到目录项。

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

2、收缩数据库

--重建索引

DBCC REINDEX DBCC INDEXDEFRAG

--收缩数据和日志

DBCC SHRINKDB DBCC SHRINKFILE

3、压缩数据库

dbccshrinkdatabase(dbname)

4、转移数据库给新用户以已存在用户权限

execsp_change_users_login 'update_one','newname','oldname' go

5、检查备份集

RESTORE VERIFYONLY fromdisk='E:dvbbs.bak'

6、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

7、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 notexpired  AND @OriginalSize = (SELECT size FROMsysfiles 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 pagesor '  CONVERT(VARCHAR(30),(size*8/1024)) 'MB'  FROM sysfiles  WHERE name = @LogicalFileName DROP TABLE DummyTrans SET NOCOUNT OFF

8、说明:更改某个表

exec sp_changeobjectowner'tablename','dbo'

9、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

10、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

案例: 有如下表,要求就裱中所有沒有及格的成績,在每次增長0.1的基礎上,使他們剛好及格:

    Name     score

    Zhangshan   80

    Lishi       59

    Wangwu      50

    Songquan    69

while((select min(score) from tb_table)<60)

begin

update tb_table set score =score*1.01

where score<60

if (select min(score) from tb_table)>60

 break

 else

   continue

end

一、基础

SQL语句先前写的时候,很容易把一些特殊的用法忘记,我特此整理了一下SQL语句操作,方便自己写SQL时方便一点,想贴上来,一起看看,同时希望大家能共同多多提意见,也给我留一些更好的佳句,整理一份《精妙SQL速查手册》,不吝赐教!

我们可以直接写成
set @strSQL = 'select count(*) as Total from [' @tblName ']
where 1=1 ' @strWhere

1、创建数据库

一、基础

2、收缩数据库
--重建索引 DBCC REINDEX DBCC INDEXDEFRAG
--收缩数据和日志 DBCC SHRINKDB DBCC SHRINKFILE

    

1、说明:创建数据库
CREATE DATABASE database-name
2、说明:删除数据库
drop database dbname
3、说明:备份sql server
--- 创建 备份数据的 device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:mssql7backupMyNwind_1.dat'
--- 开始 备份
BACKUP DATABASE pubs TO testBack
4、说明: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:create table tab_new like tab_old (使用旧表创建新表)
B:create table tab_new as select col1,col2… from tab_old definition only
5、说明:删除新表
drop table tabname
6、说明: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。
7、说明:添加主键: Alter table tabname add primary key(col)
说明:删除主键: Alter table tabname drop primary key(col)
8、说明:创建索引:create [unique] index idxname on tabname(col….)
删除索引:drop index idxname
注:索引是不可更改的,想更改必须删除重新建。
9、说明:创建视图:create view viewname as select statement
删除视图:drop view viewname
10、说明: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%’ ---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
11、说明: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。
12、说明:使用外连接
A、left outer join:
左外连接(左连接):结果集几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。

3、压缩数据库 dbcc shrinkdatabase(dbname)

CREATE DATABASE database-name

二、提升

4、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

 

1、说明: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

5、检查备份集 RESTORE VERIFYONLY from disk='E:dvbbs.bak'

2、删除数据库

2、说明: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;

6、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

    

3、说明: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..

7、日志清除
SET NOCOUNT ON
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT

drop database dbname

4、说明: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)

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)

 

5、说明: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

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)

3、备份数据库

6、说明: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

DECLARE @Counter INT,
@StartTime DATETIME,
@TruncLog VARCHAR(255)
SELECT @StartTime = GETDATE(),
@TruncLog = 'BACKUP LOG ' db_name() ' WITH TRUNCATE_ONLY'

--- 创建 备份数据的 device

use master


exec sp_addumpdevice 'disk','testBack', 'c:mssql7backupMyNwind_1.dat'


--- 开始 备份
BACKUP DATABASE pubs TO testBack

7、说明:在线视图查询(表名1:a )
select * from (SELECT a,b,c FROM a) T where t.a > 1;

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 = @Logical FileName)
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

 

8、说明: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

SELECT @Counter = @Counter 1
END
EXEC (@TruncLog)
END
ELECT '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

 

9、说明:in 的使用方法
select * from table1 where a [not] in (‘值1’,’值2’,’值4’,’值6’)

8、说明:更改某个表
exec sp_changeobjectowner 'tablename','dbo'

4、创建新表

10、说明:两张关联表,删除主表中已经在副表中没有的信息
delete from table1 where not exists ( select * from table2 where table1.field1=table2.field1 )

9、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)

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

11、说明: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 .....

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

 

12、说明: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

FETCH NEXT FROM curObject INTO @Name, @Owner
END
close curObject
deallocate curObject
GO

根据已有的表创建新表:

13、说明: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

10、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
常用精粹SQL语句大全,Sql的基础知识本领。end
案例:
有如下表,要求就裱中所有沒有及格的成績,在每次增長 0.1 的基础上,使他们刚好及格:
Name score
Zhangshan 80
Lishi 59
Wangwu 50
Songquan 69

A:create table tab_new like tab_old (使用旧表创建新表)
B:create table tab_new as select col1,col2… from tab_old definition only

14、说明:前10条记录
select top 10 * form table1 where 范围

while((select min(score) from tb_table)<60)
begin
update tb_table set score =score*1.01
where score<60
if (select min(score) from tb_table)>60
break
else
常用精粹SQL语句大全,Sql的基础知识本领。continue
end

 

15、说明: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)

5、删除新表

16、说明: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)

drop table tabname 

17、说明:随机取出10条数据
select top 10 * from tablename order by newid()

 

18、说明:随机选择记录
select newid()

6、增加一个列

19、说明:删除重复记录
Delete from tablename where id not in (select max(id) from tablename group by col1,col2,...)

Alter table tabname add column colname type

20、说明:列出数据库里所有的表名
select name from sysobjects where type='U'

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。

21、说明:列出表里的所有的
select name from syscolumns where id=object_id('TableName')

7、添加主键

22、说明: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

Alter table tabname add primary key(col) 

23、说明:初始化表table1

删除主键:

TRUNCATE TABLE table1

Alter table tabname drop primary key(col)

24、说明: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

 

三、技巧

8、创建索引

1、1=1,1=2的使用,在SQL语句组合时用的较多

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

“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 安定 ' @strWhere
2、收缩数据库
--重建索引
DBCC REINDEX
DBCC INDEXDEFRAG
--收缩数据和日志
DBCC SHRINKDB
DBCC SHRINKFILE

   删除索引

3、压缩数据库
dbcc shrinkdatabase(dbname)

drop index idxname

4、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

注:索引是不可更改的,想更改必须删除重新建。

5、检查备份集
RESTORE VERIFYONLY from disk='E:dvbbs.bak'

9、创建视图

6、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

create view viewname as select statement

7、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)

   删除视图

-- 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)

drop view viewname

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

10、几个简单的基本的sql语句

8、说明:更改某个表
exec sp_changeobjectowner 'tablename','dbo'

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%’ ---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

9、存储更改全部表

 

CREATE PROCEDURE dbo.User_ChangeObjectOwnerBatch
 @OldOwner as NVARCHAR(128),
 @NewOwner as NVARCHAR(128)
AS

11、几个高级查询运算词

DECLARE @Name   as NVARCHAR(128)
DECLARE @Owner  as NVARCHAR(128)
DECLARE @OwnerName  as NVARCHAR(128)

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。

DECLARE curObject CURSOR FOR
 select 'Name'   = name,
  'Owner'   = user_name(uid)
 from sysobjects
 where user_name(uid)=@OldOwner
 order by name

12、说明:使用外连接
A、left outer join:
左外连接(左连接):结果集几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。

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

二、提升

 FETCH NEXT FROM curObject INTO @Name, @Owner
END

1、说明: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

close curObject
deallocate curObject
GO

2、说明: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;

10、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

3、说明: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..

4、说明: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)

5、说明: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

6、说明: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

7、说明:在线视图查询(表名1:a )
select * from (SELECT a,b,c FROM a) T where t.a > 1;

8、说明: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

9、说明:in 的使用方法
select * from table1 where a [not] in (‘值1’,’值2’,’值4’,’值6’)

10、说明:两张关联表,删除主表中已经在副表中没有的信息
delete from table1 where not exists ( select * from table2 where table1.field1=table2.field1 )

11、说明: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 .....

12、说明: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

13、说明: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

14、说明:前10条记录
select top 10 * form table1 where 范围

15、说明: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)

16、说明: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)

17、说明:随机取出10条数据
select top 10 * from tablename order by newid()

18、说明:随机选择记录
select newid()

19、说明:删除重复记录
Delete from tablename where id not in (select max(id) from tablename group by col1,col2,...)

20、说明:列出数据库里所有的表名
select name from sysobjects where type='U'

21、说明:列出表里的所有的
select name from syscolumns where id=object_id('TableName')

22、说明: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

23、说明:初始化表table1

TRUNCATE TABLE table1

24、说明: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

111111111

三、技巧

1、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 安定 ' @strWhere

2、收缩数据库
--重建索引
DBCC REINDEX
DBCC INDEXDEFRAG
--收缩数据和日志
DBCC SHRINKDB
DBCC SHRINKFILE

3、压缩数据库
dbcc shrinkdatabase(dbname)

4、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

5、检查备份集
RESTORE VERIFYONLY from disk='E:dvbbs.bak'

6、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

7、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

8、说明:更改某个表
exec sp_changeobjectowner 'tablename','dbo'

9、存储更改全部表

澳门新萄京官方网站,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

10、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

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