SQL Server 2008 :: Graphical (Include Execution Plan) Left On By Default?
Jun 25, 2015
Is there a way to leave the graphical 'Include Execution Plan' on by default in SSMS? I don't know how many times I run a long-running query, say to myself, "wow, that took a while; I wonder what the execution plan looks like?" only to realize that I left it turned off. Now I have to turn it on, and wait for the query to run again. I'm guessing there's a setting in the options somewhere to always leave it on, but I'm not sure where
We have a view with many left joins. The original creators of this view might have been lazy or sloppy, I don't know. I have rewritten the query to proper inner joins where required and also nested left joins.
So rather then the following exemplary fragment
select <many items> from A left join B on B.id_A = A.id left join C on C.id_B = B.idthis now looks like select <many items> from A left join (B join C on C.id_B = B.id ) on B.id_A = A.id
Compilation time of the original view was 18s, of the new rewritten view 4s. The performance of execution is also better (not counting the compile of course). The results of the query are identical. There are about 30 left joins in the original view.
I can imagine that the optimizer has difficulty with all these left joins. But 14s is quite a big difference. I haven't looked into detail in the execution plans yet. I noticed that in both cases the Reason for Early Termination of Statement Optimization was Time Out.
Is it possible to check query execution plan of a store procedure from create script (before creating it)?
Basically the developers want to know how a newly developed procedure will perform in production environment. Now, I don't want to create it in production for just checking the execution plan. However they've provided SQL script for the procedure. Now wondering is there any way to look at the execution plan for this procedure from the script provided?
select col1, col2, col3, col4 from Table where col2=5 order by col1
I have a primary key on the column.The execution plan showing the clustered index scan cost 30% & sort cost 70%..When I run the query I got missing index hint on col2 with 95% impact.So I created the non clustered index on col2.The total executed time decreased by around 80ms but I didn't see any Index name that is using in the execution plan.After creating the index also I am seeing same execution plan
The execution plan showing the clustered index scan cost 30% & sort cost 70% but I can see the total time is reducing & Logical reads on that table is reducing.I am sure that index is useful but why there is no change in the execution plan?
I have query with an expensive Key Lookup on a joined table. The predicate is the column that I'm joining on, and the output list contains two columns from the joined table.
I've created a basic non-clustered index covering the predicate column and include-ing the two output columns. However, the execution plan ignores this, and insists on using the primary key of the joined table to do the expensive key lookup. I've tried adding the included columns to the index directly and there's no change. I've also tried running dbcc freeproccache and no change.
The benefit of the actual execution plan is that you can see the actual number of rows passing through each step - compared to the estimated number of rows.But what about the "cost percentages" ?I believe I've read somewhere that these percentages is still just an estimate and is not based on the real execution.Does anyone know this and preferable have a link to something that documents it?Thanks
Can anyone explain me simple language and easy to understand query execution plan. I am a fresher assigned to read and evaluate execution plan. i do not understand where is the problem. what percentage is considered as good sql and what percentage is considered as bad sql.
how do i understand whether there is a problem in sql or joins or index or anything else. Please explain me step by step what should be considered and what recomenendation should i give for each problem.
SELECT * FROM a LEFT OUTER JOIN b ON a.id = b.id instead of
SELECT * FROM a LEFT JOIN b ON a.id = b.id
generates a different execution plan?
My query is more complex, but when I change "LEFT OUTER JOIN" to "LEFT JOIN" I get a different execution plan, which is absolutely baffling me! Especially considering everything I know and was able to research essentially said the "OUTER" is implied in "LEFT JOIN".
As a developer, we always say "using a stored procedure, instead of a cliet side SQL statement, provides performance benefits". However, it seems it has not been true anymore since SQL Server 7.0.
See SQL online "Execution Plan Caching and Reuse" at http://msdn.microsoft.com/library/default.asp?url=/nhp/default.asp?contentid=28000409
I am quite confused with the following questions: 1. it seems since SQL 7.0, a SQL statement in client side uses the existing execution plan as a stored procedure does. That means SP doesn't has much advantage over SQL statement in terms of performance.
2. It seems, a stored procedure is not always compled ONLY once. If a stored procedure is not used for a long time, it could be kicked out from procedure cashe.
3. In order to use an existing execution plan, it seems that we have to use the fully qualified identifier, such as SELECT * FROM Northwind.dbo.Employees
instead of SELECT * FROM Employees
However, I rarely see anyone uses these kind of fully qualified references for objects both in SQL statements and SP. For example, in the sample database pubs and NorthWind, they don't use the fully qualified expression. I only see the use of it in master database.
I guess I might miss something in the issues above. I would like to get any explanation from SQL guru or anybody. Thanks a lot.
Need table has clusted index on needid column and NeedCategory have composite clustered index on needid and categoryid.
Now take a look on following query and execution plan for the query.
SELECT N.NeedId,N.NeedName,N.ProviderName FROM dbo.Need N JOIN dbo.NeedCategory NC ON nc.NeedId = n.NeedId WHERE IsActive=1 AND CategoryId= 2 ORDER BY NeedName
* Clustered index scan on need table is happens for Isactive= 1.
* Clustered index scan on needcategory table is happens for CategoryId=2
My question is,
1. Why scan happens before the join occurs? if it happens after join then the filter would be lighter. Even if optimizer chooses the scan to execute first.
2. Is there any chance to rearrange the execution plan manually?
Hi I am having a query SELECT Dur1.rootId FROM DurableEventTab Dur1 WHERE (Dur1.dev_ReferenceClusterRoot = 'iyrwd.52' ) AND Dur1.dev_Action = 'Order:Ordered') AND (Dur1.dev_Active = 1) AND (Dur1.dev_PurgeState = 0) AND (Dur1.dev_PartitionNumber = 0)
This table has a primary key : aribapk11 and the indexes on the dev_ReferenceClusterRoot, dev_Action,dev_purgestate .
Now when I fire this query the query execution plan is actaull doing a Clustered Index scan on the PK :aribaPK11 . What I was expecting was an index seek on the key defined on dev_referenceClusterRoot. Please not the index seek is the behaviour in sql server 2000.
Any idea what is going wrong ?
Clustered Index Scan(OBJECT:([typhoon1902].[dbo].[DurableEventTab].[AribaPK7] AS [Dur1]), WHERE:([typhoon1902].[dbo].[DurableEventTab].[dev_Active] as [Dur1].[dev_Active]=(1.) AND [typhoon1902].[dbo].[DurableEventTab].[dev_PurgeState] as [Dur1].[dev_PurgeState]=(0) AND [typhoon1902].[dbo].[DurableEventTab].[dev_PartitionNumber] as [Dur1].[dev_PartitionNumber]=(0) AND [typhoon1902].[dbo].[DurableEventTab].[dev_ReferenceClusterRoot] as [Dur1].[dev_ReferenceClusterRoot]='iyrwd.52' AND [typhoon1902].[dbo].[DurableEventTab].[dev_Action] as [Dur1].[dev_Action]=N'Order:Ordered')) 0 0 Clustered Index Scan Clustered Index Scan OBJECT:([typhoon1902].[dbo].[DurableEventTab].[AribaPK7] AS [Dur1]), WHERE:([typhoon1902].[dbo].[DurableEventTab].[dev_Active] as [Dur1].[dev_Active]=(1.) AND [typhoon1902].[dbo].[DurableEventTab].[dev_PurgeState] as [Dur1].[dev_PurgeState]=(0) AND [typhoon1902].[dbo].[DurableEventTab].[dev_PartitionNumber] as [Dur1].[dev_PartitionNumber]=(0) AND [typhoon1902].[dbo].[DurableEventTab].[dev_ReferenceClusterRoot] as [Dur1].[dev_ReferenceClusterRoot]='iyrwd.52' AND [typhoon1902].[dbo].[DurableEventTab].[dev_Action] as [Dur1].[dev_Action]=N'Order:Ordered') [Dur1].[rootId] 1 0.00386574 0.0002263 71 0.00409204 [Dur1].[rootId] PLAN_ROW 0 1
Normally it is recommended to leave an empty partition on both the front and back ends of a table to avoid data movement when merging/splitting. But I have some questions based on my scenario, which is a table partitioned by a load date, so all records in a partition contain the same date, not a range of dates.
If I use range left, once I switch out the first partition it would become empty, so would there be data movement when I merge it into the next partition? The real issue though is that we will not just be removing the first partition, but "random" partitions throughout the table. Will this work?
If I use range right, when I split the last partition to create a new one it doesn't seem there would be any data movement there either. Am I missing something?
Basically I'm wondering if I should use range left or right. Most recommend using right, but then the boundary value is not the value in the partition. This could potentially result in someone deleting the wrong data if they are not careful. So is there any reason not to use left in my scenario?
I did a test of removing a partition in the middle and it worked just fine; this was using range right. I have about 6 million rows per partition. I also tested splitting at the end and it worked fine. I'll rebuild it with range left and test.
I'm new to using SQL Server. I've been asked to optimize a series of scripts that queries over 4 millions records. I've managed to add indexes and remove a cursor, which increased performance. Now when I run the execution plan, the only query that cost is a DELETE statement from the main table. It shows a SORT which cost 71%. The table has 2 columns and a unique index. Here is the current index:
ALTER TABLE [dbo].[Qry] ADD CONSTRAINT [Qry_PK] PRIMARY KEY NONCLUSTERED ( [QryNum] ASC, [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = ON, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO
Question: Will the SORT affect the overall performance? If so, is there anything I should change within the index that would speed up my query?
I have imported a txtfile to access and have some problem making the data appear in my wanted way. I want to shift the cells in the first row one step to the left, i.e to overwrite the zeros with the left value. Then I want to assign the first row values as field names.
Current data
Field1 Field2 Field3 Field4 Field5 0 Name Major Sector Hi karl per anna
I have a person table with 1 billion rows on it, partitioned equally at 10 million rows per partition. The primary key constraint is a composite of an identity column and ssn( char(11) ) with the partitioning column built on the SSN.
This is built on my home grown workstation:
Microsoft 2008 Server 64 bit, Microsoft SQL server 2008 64 bit, Intel 2.66 quad core, 8 gb ram, Os/ raid 1, data on 6 drives hardware/software raid 50, transaction logs on 4 drive raid 10, all drives sata II/ 3gb burst.
I have updated statistics on the table and I have 2 queries that give clustered index seek , one never comes back before I get impatient, the other comes back instantly, and the showplan looks the same for both queries.
SELECT *
FROM Person
WHERE PersonKey > -1 and SSN = '219-09-3987'
AND
SELECT TOP 100 PERCENT *
FROM Person
WHERE PersonKey > -1 and SSN = '219-09-3987'
Incidentally the query with the top 100 percent is the one that returns instantly.
I am puzzled
1) Why the estimated plan looks the same
2) Why a top 100 Percent query is faster than one without it
I am trying to erase some erroneous bad data in my table. The description column has a lot of </div>oqwiroiweuru</a> weird data attached to it, i want to keep the data to the left of where the </div> erroneous data begins
update MyTable set Description = LEFT(Description(CHARINDEX('<',Description)-1)) where myid = 1
that totally works.
update MyTable set Description = LEFT(Description(CHARINDEX('<',Description)-1)) where myid >= 2
gives me a Invalid length parameter passed to the LEFT or SUBSTRING function. The statement has been terminated error.
In sp_create_plan_guide documentation, it's written:
When SQL Server matches the value of statement_text to batch_text and @parameter_name data_type [,...n ], or if @type = 'OBJECT', to the text of the corresponding query inside object_name, the following string elements are not considered:
White space characters (tabs, spaces, carriage returns, or line feeds) inside the string. Comments (-- or /* */). Trailing semicolons
On SQL Server 2008 SP3, I created a plan guide for a query. Now, if I execute the query exactly how it was defined in the plan guide, SQL Server match it and use the plan guide to optimize the query.
However, if I add just a space between a column name and an operator in the WHERE clause, the plan guide is ignored. How come it doesn't ignore the extra space, like mentioned in the documentation?
Looking at an execution plan today I noticed something I've not seen before. The plan includes a non clustered index seek, followed by a RID lookup on the heap. The output list for the index seek contains the expected "Bmk" column (in this case "Bmk1473"), but also includes "IsBaseRow1475". This isn't a column from the table.
One of my programmers changed their database from full to Simple recovery. Saw that my job that backs up the Full Recovery mode databases failed, so I moved that database to my Simple database backup job plan and removed it from the Full Recovery job. I am unable to remove the db from the Transaction Log task on the Full Plan because when I try to edit that job "Databases with Simple Recovery will be excluded"
My transaction log backups are still failing with the following error: "The statement BACKUP LOG is not allowed while the recovery model is SIMPLE. Use BACKUP DATABASE or change the recovery model using ALTER DATABASE. BACKUP LOG is terminating abnormally.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.Just want to remove that database so my Full Recovery backup job does not try to back it up.
I have inherited a server on which is a maintenance plan with two subplans on different schedules. In each subplan there are Execute T-SQL tasks with scripts for index rebuilds. Each task is set up with a Completion arrow to the next task and a Failure arrow to a Notify Operator Task. I was asked to add a task for index rebuilds to a specific subplan for a specific database, which is what the other tasks also do. I discovered that my task was failing but the others were fine. No notification was sent about my task failing even though the job is marked in MSDB as a failed job. I have sent a test email using the "Send Test Email..." option when right clicking Database Mail in SSMSand I receive an email so I know Database Mail works.
I set up a test job to model the index job that I can't get notifications from. I have two T-SQL tasks that just select the top row from a small table. The first task has a syntax error that I did so it would fail. I have a failure arrow to a Notify Operator Task and a Completion arrow to another T-SQL task with no syntax error which has a Success arrow to a Notify Operator task. As expected, when I execute this job I receive one failure email and one success email.
The only other troubleshooting step I know to try is to add a Notify Operator task before my failing task. That Notify Operator task will hopefully fire to tell me that the previous step was successful. I am not having problems with the other steps so I was just thinking I would try to get the subplan to send me a success email about one of the steps that has been working fine.
I'm new to SQL server but familiar enough with databases to know this doesn't seem right. Here's the situation: I have a table with real estate property information. There are about 650,000 rows in it. I have a nonclustered non-unique index on the city where the property is located. There are about 40 unique values in this index.
I do a simple query like: SELECT city,address from propinfo where city= 'CARLSBAD'. The query will return about 4,000 rows. The problem is that the execution plan that it chooses is to do a full table scan. I.E. Even though there is an index on City, it chooses to look through 650,000 rows rather than do an index seek. Something sounds inefficient here. BTW, this happens in both SQL 7 and SQL 2000. Can anyone explain why this happens? I've got to think that SQL Server is more efficient here.
Hello, I have been looking at the execution plan for a procedure call and the select, compute scalar, stream aggregates, constant scan, nested loops, asserts are all at 0% cost, the PK costs are 2% apart from a rogue 7% and a few 20%, tables scans are all at 23%. The query cost realtive to the batch is 100%. What does this all mean? I have put non-clustered indexes on all the table attributes that are involved in the select statements but this has made no difference, i am guessing this is because my tables are not heavily populated and i may have seen a difference if i had thousands of entries in the tables the select statements acted on, is this assumption correct? Does anyone else bother using the execution plan to tweak there DB or is it a negligible tool?
In sql server 2005 management studio where do I find the option to run the sql query in the query analyser and also show the execution plan? At present I see the option under Query menu which is "Display estimated Execution plan" which only shows the plan but does not execute the query.
Does anyone know of a good way to copy the execution plan when using "Include Actual Execution Plan"? I often need to copy this and mail it.
I know I can use PrintScreen button, but I need a more efficient way to do this. If I just could rightclick the execution plan and select "Copy" and get complete plan it would be great.
Which of the following does NOT cause the execution plan of a query to berecompiled ?- new column is added to a table accessed by a query OR- index used by a query has been dropped from the database OR- query perfoms a join to return data from multiple tables OR- significant amount of data in a table has been mofified
Hi,I have a table-valued user defined function (UDF) my_fnc.The execution of statement "select * from my_fnc" takes much longertime than runnig the code inside my_fnc (with necessary changes).What can be the reason?How can I see an execution plan used for UDF?Thanks a lotMartin
I am replicating a stored procedure execution, which builds and executes the following dynamic SQL command:
IF EXISTS (select * from MyDB..sysfiles sf (nolock) where name = 'MyDB_201201') ALTER DATABASE [MyDB] REMOVE FILE [MyDB_201201] IF EXISTS (select * from MyDB..sysfilegroups sfg (nolock) where groupname = 'MyDB_201201' and sfg.groupname not in( SELECT distinct fg.name file_group_name
[Code] ....
I can run this SP with no errors on both the publisher and the subscriber. However, when I try to replicate the execution of this SP, I get an error in replication monitor:
ALTER DATABASE statement not allowed within multi-statement transaction. (Source: MSSQLServer, Error number: 226)
How can I change my code to workaround this? Perhaps some explicit transactions?
Hi,I want to access the real execution plan via my webapplication after I have executed an SQL statement. I know how to get the estimated execution plan:1 cmd.CommandText = "SET SHOWPLAN_XML ON";2 cmd.ExecuteNonQuery();3 4 cmd.CommandText = myStatement;5 SqlDataReader dataReader = cmd.ExecuteReader();6 7 String plan = String.Empty;8 9 while (dataReader.Read()) {10 plan += dataReader.GetSqlString(0).ToString();11 }12 13 cmd.CommandText = "SET SHOWPLAN_XML OFF";14 cmd.ExecuteNonQuery();I want do compare the estimated costs with the real costs of the same statement. If I change code line 1 an 13 to "SET STATISTICS XML [ON|OFF]" the string "plan" will contain the result of the submitted SELECT statement, but I just need to get the plan and not the result itself. Thanks in Advance,Dominik
