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一些sql三

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全栈程序员站长
发布2022-07-15 15:51:06
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发布2022-07-15 15:51:06
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大家好,又见面了,我是全栈君,今天给大家准备了Idea注册码。

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 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

— http://hovertree.com/menu/sqlserver/ 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 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

发布者:全栈程序员栈长,转载请注明出处:https://javaforall.cn/120472.html原文链接:https://javaforall.cn

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原始发表:2021年12月,如有侵权请联系 cloudcommunity@tencent.com 删除

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