>>>>Hi,
>>>>
>>>>I wonder, does reindexing SQL Server database improves performance? If yes, how often do you do it?
>>>>I Googles the steps and it shows the steps for one table. Is there a way to reindex all tables at once?
>>>>
>>>>TIA
>>>
>>>Yes, can. Each index can be fragmented. How much? It's depends on list of columns, number of writes, etc.
>>>
>>>

>>>
>>>-- list fragmented indexes
>>>SELECT ps.database_id, ps.OBJECT_ID, ps.index_id, AA.Name, b.name, ps.avg_fragmentation_in_percent
>>>FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL, NULL, NULL) AS ps
>>>     INNER JOIN sys.indexes AS b ON ps.OBJECT_ID = b.OBJECT_ID AND ps.index_id = b.index_id
>>>     INNER JOIN sys.tables as AA ON b.OBJECT_ID=AA.OBJECT_ID
>>>WHERE ps.database_id = DB_ID() AND ps.avg_fragmentation_in_percent>30 AND NOT b.name IS NULL
>>>ORDER BY 6 DESC
>>>GO
>>>
>>>--rebuild fragmented indexes
>>> DECLARE @lorsData CURSOR
>>> DECLARE @lcTABNAME VARCHAR(128), @lcNAME VARCHAR(128), @lfDFG FLOAT
>>> SET @lorsData=CURSOR LOCAL READ_ONLY FOR 
>>>    SELECT AA.Name, b.name,ps.avg_fragmentation_in_percent
>>>    FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL, NULL, NULL) AS ps
>>>         INNER JOIN sys.indexes AS b ON ps.OBJECT_ID = b.OBJECT_ID AND ps.index_id = b.index_id
>>>         INNER JOIN sys.tables as AA ON b.OBJECT_ID=AA.OBJECT_ID
>>>    WHERE ps.database_id = DB_ID() AND ps.avg_fragmentation_in_percent>30 AND NOT b.name IS NULL
>>>    ORDER BY 3 DESC
>>>
>>> OPEN @lorsData
>>> WHILE 0 = 0 BEGIN
>>>   FETCH NEXT FROM @lorsData INTO @lcTABNAME, @lcNAME, @lfDFG
>>>   IF @@FETCH_STATUS <> 0 BREAK
>>>
>>>   BEGIN TRY 
>>>    EXEC('ALTER INDEX ['+@lcNAME+'] ON ['+@lcTABNAME+'] REBUILD WITH(ONLINE = ON)')
>>>    PRINT CAST(@lfDFG AS VARCHAR(30))+' ALTER INDEX ['+@lcNAME+'] ON ['+@lcTABNAME+'] REBUILD /*WITH(ONLINE = ON)*/'
>>>   END TRY 
>>>   BEGIN CATCH
>>>     PRINT 'FAILED: '+@lcTABNAME+' '+@lcNAME 
>>>   END CATCH
>>>   
>>> END
>>> CLOSE @lorsData
>>> DEALLOCATE @lorsData
>>>GO
>>>

>>>
>>>MartinaJ
>>
>>Thank you, Martina. I will run your code on my SSMS first, before attempting it on the customer SQL Server.
>>Two follow-up questions, please.
>>1. Should - as far as you know - the defragmentation of indexes (running your code above or another way) be done by a DBA?
>>2. Do you think it is a good idea to include the above code in the application (VFP 9) feature? That is, so that the end user can run it when they feel the data is slow?
>>Thank you.
>
>Dmitry,
>
> You can write stored procedure a set SQL job with schedule each first day in month in 00:00 which run your procedure.
>And if you have stored procedure, you can calls it if you/customer need.
>
>MartinaJ

Thank you, Martina! I will bring it up to the customer who is experiencing the slow down. Honestly, I don't even know if their slowness is caused by the index defragmentation. But I am trying different things.