游标使用系列二

标签：HERE   nvarchar   执行   span   sele   while   where   DBName   print   

索引重建的情况

对一个数据库所有的表执行索引重建：

Declare T_cursor cursor

for

select name from sys.tables

Declare @T_name varchar(50)

open T_cursor

fetch next from T_cursor into @T_name;

while @@fetch_status=0

Begin

Declare I_cursor cursor

for

select a.name,b.name,c.avg_fragmentation_in_percent from sys.tables a

join sys.indexes b on a.object_id=b.object_id

join sys.dm_db_index_physical_stats(DB_ID(N‘student_score‘),object_id(@T_name),null,null,null) c on b.object_id=c.object_id and b.index_id=c.index_id;

Declare @Table_name nvarchar(100),@Index_name nvarchar(100),@Avg_Fra int,@SQL nvarchar(100)

open I_cursor

fetch next from I_cursor into @Table_name,@Index_name,@Avg_Fra

while @@FETCH_STATUS=0

Begin

       if @Avg_Fra>30

       begin

              set @SQL=‘Alter index ‘+@Index_name+‘ on dbo.‘+@Table_name+‘ Rebuild with (fillfactor=75)‘

       end

       else

       Begin

              set @SQL=‘Alter index ‘+@Index_name+‘ on dbo.‘+@Table_name+‘ Reorganize‘

       end

       Print @SQL

       Exec (@SQL)

       fetch next from I_cursor into @Table_name,@Index_name,@Avg_Fra

end

close I_cursor

deallocate I_cursor

fetch next from T_cursor into @T_name;

end

close T_cursor;

deallocate T_cursor;

对所有数据库所有的表执行索引重建(对索引碎片比率进行判断后执行重建或重组)：

Declare DB_cursor cursor

for

select name from sys.databases where name  name in

(N‘school_new‘,N‘student_score‘)

declare @DBname varchar(50)

open DB_cursor

fetch next from DB_cursor into @DBname;

while @@FETCH_STATUS=0

Begin

declare @CMD varchar(1000)

set @CMD=     

                      ‘use [‘+@DBname+‘];‘+‘

                                                          Declare T_cursor cursor

                                                          for

                                                          select name from sys.tables‘

                                                          Exec (@CMD)

                                                          Declare @T_name varchar(50)

                                                          open T_cursor;

                                                          fetch next from T_cursor into @T_name;

                                                          while @@fetch_status=0

                                                          Begin

                                                          Declare I_cursor cursor

                                                          for

                                                          select a.name,b.name,c.avg_fragmentation_in_percent from sys.tables a

                                                          join sys.indexes b on a.object_id=b.object_id

                                                          join sys.dm_db_index_physical_stats(DB_ID(@DBname),object_id(@T_name),null,null,null) c on b.object_id=c.object_id and b.index_id=c.index_id;

                                                          Declare @Table_name nvarchar(100),@Index_name nvarchar(100),@Avg_Fra int,@SQL nvarchar(100)

                                                          open I_cursor

                                                          fetch next from I_cursor into @Table_name,@Index_name,@Avg_Fra

                                                          while @@FETCH_STATUS=0

                                                          Begin

       if @Avg_Fra>30

       begin

              set @SQL=

              ‘Alter index ‘+@Index_name+‘ on dbo.‘+@Table_name+ ‘ Rebuild with (fillfactor=75)‘

       end

       else

       Begin

              set @SQL=

              ‘Alter index ‘+@Index_name+‘ on dbo.‘+@Table_name+‘  REORGANIZE‘

       end

       Print @SQL

       Exec (@SQL)

       fetch next from I_cursor into @Table_name,@Index_name,@Avg_Fra

end

close I_cursor

deallocate I_cursor

fetch next from T_cursor into @T_name;

end

close T_cursor;

deallocate T_cursor;

fetch next from DB_cursor into @DBname;

end

close DB_cursor

deallocate DB_cursor;

游标使用系列二

标签：HERE   nvarchar   执行   span   sele   while   where   DBName   print   

原文地址：https://www.cnblogs.com/LC0507/p/11177653.html