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  • 《精妙SQL速查手册》

    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!
    
    
    一、基础
    
    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:\mssql7backup\MyNwind_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 ALLUNION 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 ALLEXCEPT 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 ALLINTERSECT 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。
    
    二、提升
    
    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
    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;
    
    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
    
    三、技巧
    
    11=11=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 
    
    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
    
    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 
    
    存储过程中经常用到的本周,本月,本年函数 
    Dateadd(wk,datediff(wk,0,getdate()),-1) 
    Dateadd(wk,datediff(wk,0,getdate()),6) 
    
    Dateadd(mm,datediff(mm,0,getdate()),0) 
    Dateadd(ms,-3,dateadd(mm,datediff(m,0,getdate())+1,0)) 
    
    Dateadd(yy,datediff(yy,0,getdate()),0) 
    Dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0)) 
    
    上面的SQL代码只是一个时间段 
    Dateadd(wk,datediff(wk,0,getdate()),-1) 
    Dateadd(wk,datediff(wk,0,getdate()),6) 
    就是表示本周时间段. 
    下面的SQL的条件部分,就是查询时间段在本周范围内的: 
    
    Where Time BETWEEN Dateadd(wk,datediff(wk,0,getdate()),-1) AND Dateadd(wk,datediff(wk,0,getdate()),6) 
    而在存储过程中 
    select @begintime = Dateadd(wk,datediff(wk,0,getdate()),-1) 
    select @endtime = Dateadd(wk,datediff(wk,0,getdate()),6)
    
    
    查表:
    if not exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[S_DBUpdateLog]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
    begin
        CREATE TABLE [dbo].[S_DBUpdateLog] (
            [ID] [int] IDENTITY (1, 1) NOT NULL PRIMARY KEY  NONCLUSTERED,
            [DBUpdateDate] [datetime] NOT NULL ,
            [Remark] [nvarchar] (100) COLLATE Chinese_PRC_CI_AS NOT NULL DEFAULT ('')
        ) ON [PRIMARY]
    end
    
    查字段
    
    if not   exists   (select   *   from   dbo.syscolumns   where   id   =   object_id(N'[dbo].[A01_Function]')   and   name   =   'A01_ZaiRenZhiWu')   
    begin
     alter table  A01_Function ADD A01_ZaiRenZhiWu bit NULL --增加列
    end
    GO
    
    
    查存储过程
    
    
    if exists (select * from dbo.sysobjects 
            where id = object_id(N'[dbo].[s_CopyRoleInfo]') 
            and OBJECTPROPERTY(id, N'IsProcedure') = 1)
    Begin
        DROP PROCEDURE [dbo].[s_CopyRoleInfo]
    End
    
    
    
    --增加主键
    if not exists (select * from sysobjects  where parent_obj = object_id( N'[dbo].[A01_Function_GBTJ]') and OBJECTPROPERTY(id, N'CnstIsClustKey') = 1 )
    begin
    ALTER TABLE dbo.A01_Function_GBTJ ADD CONSTRAINT
        PK_A01_Function_GBTJ PRIMARY KEY CLUSTERED 
        (
        A00
        ) WITH( STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
    end
    
    --增加外键
    if not exists (select * from sysobjects  where  name ='FK_A01_Node_z_nodetree' and parent_obj = object_id( N'[dbo].[A01_Node_r]') and OBJECTPROPERTY(id, N'CnstIsColumn') = 1 )
    begin
        alter table dbo.[A01_Node_r]
        add constraint FK_A01_Node_z_nodetree 
        foreign key(NodeID) references dbo.z_nodetree(NodeID) 
        on delete cascade 
    end
    
    
    --增加列
    if   exists   (select   *   from   dbo.syscolumns   where   id   =   object_id(N'[dbo].[BJJA60]')   and   name   =   'BJXBJJA6001C')   
    begin
    --alter table  BJJA60 drop column BJXBJJA6001C -- 删除列
     --alter table  BJJA60 ADD BJXBJJA6001C uniqueidentifier NULL --增加列
    end
    
    --遍历一张表
    declare @Col1 uniqueidentifier
    declare Cursor1 cursor
        local Forward_only static
        for  
        select a00 from a01 
        open Cursor1
            begin
                fetch next  from Cursor1  into @Col1
                while @@FETCH_STATUS = 0
                begin
                    --exec syna01 @Col1
                    fetch next from Cursor1 into  @Col1
                end
            end
    
    
    DECLARE curs CURSOR
        FOR 
        SELECT [dbo].[BAP_ROLE].[NAME] FROM [dbo].[bap_user_role]
        INNER JOIN [dbo].[BAP_ROLE] ON [dbo].[bap_user_role].[Role_ID] = [dbo].[BAP_ROLE].[Role_ID]
        WHERE [dbo].[bap_user_role].[User_ID]=@user_id
        OPEN curs 
            BEGIN
                FETCH NEXT FROM curs INTO @name
                WHILE @@FETCH_STATUS = 0
                    BEGIN 
                        IF(@name<>'')
                        BEGIN
                            SET    @Return=@Return+','+@name
                        END
                        FETCH NEXT FROM curs INTO @name
                    END
            END
    close curs
    deallocate curs
    
    
    
    
    
    
    
    
    
    
    
    
    
    if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[Procedure]') 
        and OBJECTPROPERTY(id, N'IsProcedure') = 1)
    drop procedure [dbo].[Procedure]
    GO
    
    SET QUOTED_IDENTIFIER ON 
    GO
    SET ANSI_NULLS OFF 
    GO
    
    CREATE PROCEDURE
    
    ...
    go
    
    SET QUOTED_IDENTIFIER OFF 
    GO
    SET ANSI_NULLS ON 
    GO
    
    
    
    
    
    
    
    
    USE [AFTzzb30]
    GO
    DBCC SHRINKDATABASE(N'AFTzzb30', 10, TRUNCATEONLY)
    
    BACKUP DATABASE [AFTzzb30] TO  DISK = N'H:\各项目组使用数据库共享区2\丰台扩展项目\AFTzzb30_backup_201010291406.bak' WITH  RETAINDAYS = 14, NOFORMAT, NOINIT,  NAME = N'AFTzzb30_backup_20101029140647', SKIP, REWIND, NOUNLOAD,  STATS = 10
    
    
    
    
    
    截断数据库日志
    bACKUP LOG  SDLQ_DNT26  WITH  TRUNCATE_ONLY
    DBCC  ShrinkDatabase(SDLQ_DNT26)
    
    
    
    
    --exec sp_detach_db zzb30,true --卸除这个DB在MSSQL中的注册信息 
    --到日志的物理文件所在的目录中去删除该日志文件或者将该日志文件移出该目录 
    exec sp_attach_single_file_db zzb30,'d:\9g\zzb30\zzb30.mdf' 
    
    
    
    
    
    exec   sp_addlinkedserver   'link1','','sqloledb','10.4.41.9'--链接到10.4.41.9服   务器,链接名:link1   
    
      exec   sp_addlinkedsrvlogin   'link1','false',null,'sa','sql'--登陆到链接服务器   
      exec   sp_serveroption   'link1','rpc   out','true'--允许调用链接服务器上的存储过程   
      go   
        
        
      --查询示例   
      select   *   from   link1.数据库名.dbo.表名   
        
      --导入示例   
      select   *   intofrom   link1.数据库名.dbo.表名   
        
        
        
      --结束查询   
      exec   sp_dropserver   'link1','droplogins'--删除链接服务器   
        
      go
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  • 原文地址:https://www.cnblogs.com/fuckcn/p/3114459.html
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