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DB太大?一键帮你收缩所有DB文件大小(Shrink Files for All Databases in SQL Server)

本文介绍一个简单的SQL脚本,实现收缩整个Microsoft SQL Server实例所有非系统DB文件大小的功能。

 

作为一个与SQL天天打交道的程序猿,经常会遇到DB文件太大,把空间占满的情况:

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而对于开发测试人员来说,如果DB数据不是特别重要的话,不会特意扩大磁盘空间,而是直接利用SQL的Shrink File功能缩小DB文件大小,详见:https://docs.microsoft.com/en-us/sql/relational-databases/databases/shrink-a-file。

 

这里介绍一个脚本,支持一键收缩整个SQL Server实例上所有非系统DB文件大小。

脚本支持功能和相关逻辑如下:

  • 五个系统DB(master、model、msdb、tempdb、Resource)不会执行Shrink File操作;
  • 如果DB的Recovery Model是FULL或者BULK_LOGGED,会自动改成SIMPLE,Shrink File操作后再改回原来的;
  • 只会对DB状态为ONLINE的DB进行Shrink File操作;
  • DB的所有文件,包括数据文件和日志文件都会被执行收缩操作;
  • 执行SQL脚本的用户需要有sysadmin或者相关数据库的DBO权限。

脚本如下:

 1 -- Created by Bob from http://www.cnblogs.com/lavender000/ 2 use master 3 DECLARE dbCursor CURSOR for select name from [master].[sys].[databases] where state = 0 and is_in_standby = 0; 4 DECLARE @dbname NVARCHAR(255) 5 DECLARE @recoveryModel NVARCHAR(255) 6 DECLARE @tempTSQL NVARCHAR(255) 7 DECLARE @dbFilesCursor CURSOR 8 DECLARE @dbFile NVARCHAR(255) 9 DECLARE @flag BIT10 11 OPEN dbCursor12 FETCH NEXT FROM dbCursor INTO @dbname13 14 WHILE @@FETCH_STATUS = 015 BEGIN16     if((@dbname <> master) and (@dbname <> model) and (@dbname <> msdb) and (@dbname <> tempdb) and (@dbname <> Resource))17     begin18         print(‘‘)19         print(Database [ + @dbname + ] will be shrinked log...)20         SET @flag = 121         SET @recoveryModel = (SELECT recovery_model_desc FROM sys.databases WHERE name = @dbname)22         if((@recoveryModel = FULL) or (@recoveryModel = BULK_LOGGED))23         begin24             SET @tempTSQL = (select CONCAT(ALTER DATABASE [, @dbname, ] SET RECOVERY SIMPLE with no_wait))25             EXEC sp_executesql @tempTSQL26             if (@@ERROR = 0)27             begin28                 print(    Database [ + @dbname + ] recovery model has been changed to ‘‘SIMPLE‘‘.)29                 SET @flag = 130             end31             else32             begin33                 print(Database [ + @dbname + ] recovery model failed to be changed to ‘‘SIMPLE‘‘.)34                 SET @flag = 035             end36         end37 38         if(@flag = 1)39         begin40             SET @tempTSQL = (select CONCAT(use [, @dbname, ]))41             EXEC sp_executesql @tempTSQL            42             SET @dbFilesCursor = CURSOR for select sys.master_files.name from sys.master_files, [master].[sys].[databases] where databases.name = @dbname and databases.database_id = sys.master_files.database_id43             open @dbFilesCursor44             FETCH NEXT FROM @dbFilesCursor INTO @dbFile45             WHILE @@FETCH_STATUS = 046             BEGIN47                 SET @tempTSQL = (select CONCAT(use [, @dbname, ] DBCC SHRINKFILE (N‘‘‘, @dbFile, ‘‘‘) with NO_INFOMSGS))48                 EXEC sp_executesql @tempTSQL49                 if(@@ERROR = 0)    print(        Database file [ + @dbFile + ] has been shrinked log successfully.)50                 FETCH NEXT FROM @dbFilesCursor INTO @dbFile51             END52             CLOSE @dbFilesCursor53             DEALLOCATE @dbFilesCursor54 55             if(@recoveryModel <> SIMPLE)56             begin57                 -- Finally changed back58                 SET @tempTSQL = (select CONCAT(ALTER DATABASE [, @dbname, ] SET RECOVERY , @recoveryModel,  with no_wait))59                 EXEC sp_executesql @tempTSQL60                 if (@@ERROR = 0)61                 begin62                     print(    Database [ + @dbname + ] recovery model has been changed back to ‘‘‘ + @recoveryModel + ‘‘‘‘)63                 end64                 else 65                 begin66                     print(    Database [ + @dbname + ] recovery model failed to be changed back to ‘‘‘ + @recoveryModel + ‘‘‘‘)67                 end68             end69         end70     end71 FETCH NEXT FROM dbCursor INTO @dbname72 END73 74 CLOSE dbCursor75 DEALLOCATE dbCursor

执行完效果如下:

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Note:

  • 如果不放心使用,可提前备份相关数据库;
  • 使用前请仔细阅读脚本支持功能和相关逻辑,如与自己需求不符,请不要使用该脚本,或者请根据自己需求自行修改脚本;
  • 脚本为简易脚本,仅用于测试学习,可能有BUG,不可生产环境使用,如有错误,请留言。

 

[原创文章,转载请注明出处,仅供学习研究之用,如有错误请留言,谢谢支持]

[原站点:http://www.cnblogs.com/lavender000/p/6882741.html,来自永远薰薰]

DB太大?一键帮你收缩所有DB文件大小(Shrink Files for All Databases in SQL Server)