Find last statistics updated date detail ?–Maintenance TIP #59

 

Problem:- One of the pain point in any SQL engineer  is “Performance”. There are various reasons due to which your SQL Server database is slow.

One of the possible reason is your maintenance.   You don’t know when statistics last updated and take further step if those are not updated

Solution:-

Here we have simple query to find when the statistics was last updated for a table.

SELECT o.name,
       i.name AS [Index Name], 
       STATS_DATE(i.[object_id], i.index_id) AS [Statistics Date],
       s.auto_created,
       s.no_recompute,
       s.user_created
FROM sys.objects AS o WITH (NOLOCK)
INNER JOIN sys.indexes AS i WITH (NOLOCK) ON o.[object_id] = i.[object_id]
INNER JOIN sys.stats AS s WITH (NOLOCK)   ON i.[object_id] = s.[object_id]
                      AND i.index_id = s.stats_id
WHERE o.[type] = 'U'
ORDER BY STATS_DATE(i.[object_id], i.index_id) ASC;  

When you run it you will find last statistics update date if it is too old it means you have to run the maintenance for those tables.

see below screenshot which I run on my machines adventureworks2012 database.

I am sure you will analyze your database tables stats and run maintenance accordingly.

I hope this tip may help you some where.

Enjoy !!!

Rj!!

Maintenance of fragmented Heap table–TIP #55

 

Friends,

In last post  post #54  we understood what is a Heap table. Now the challenge is what if this table is highly fragmented so.

Now our task is to run maintenance of this highly fragmented table.

So you have to run following command

“ALTER TABLE  TABLENAME REBUILD;

For example  I run the Rebuild for  Adventureworks2012 database’s heap table which we found in post #54.

See below snap for detail

 

So, with this REBUILD command the table is rebuild and the fragmentation issue resolved.

I hope it may help you some where.

Thanks & Enjoy!!!

RJ!!

Performance tips - How to determine last statistics update in table ? TIP #46

Hi,

For maintenance purpose we need to determine when the stats last update and analyze the data and if data is out dated then we need to update the stats.

To determine this we need to run the following scripts

SELECT OBJECT_NAME(s.object_id) AS [ObjectName]
      ,s.name AS [StatisticName]
      ,STATS_DATE(s.object_id, [stats_id]) AS [StatisticUpdateDate]
FROM sys.stats s
INNER JOIN sys.objects obj ON obj.object_id = s.object_id
AND obj.type IN ('U','V')
ORDER BY STATS_DATE(s.object_id, [stats_id]) Asc,obj.name

 

For example I run the following code in adventurework2012

 

So according to update status date we do update statistics of those tables in database.

I hope this tip will help you.

Enjoy !!!

RJ