"Complex queries, however, such as those in decision support systems,
can reference large numbers of rows in base tables and aggregate large
amounts of information into relatively concise aggregates (such as sums
or averages). SQL Server 2000 supports creating a clustered index on a
view that implements such a complex
query. When the CREATE INDEX statement is executed, the result set of
the view SELECT is stored permanently in the database. Future SQL
statements that reference the view will have substantially better
response times. Modifications to the base data are automatically
reflected in the view."
My question arises from the last sentence. At what point are the views
updated with the new data? If I am running a transaction that updates
some dependent tables, is there a performance impact while the indexed
views are updated?
Hello, I'm currently performance tuning a table with 100 million rows in it (about 18 GB of data) and would like to know if -
1. Is the table too large to be performance tuned. Is it better to just redesign the schema ? 2. Can using techniques as indexed views really help me with tuning such a table. 3. How long would it take to create a clustered, non clustered index on a varchar column (for instance) on a table with 100 million rows ? (i know this is a function of hardware as well - let's assume i'm using afairly maxed out DL 360 - i.e. dual processor with 4 GB of memory)
I am looking for a little insight. I am using an SQL Server database created by a third party vendor. There are certain columns in a given table that I query for quite often. To speed things up, I created an indexed view.
Now I can no longer insert into the base table. Attempting an insert causes a SQL error stating that the system properties ARITHABORT and NUMERIC_ROUNDABORT are incorrect. If I remove the index from my view, the inserts work just fine.
Can somebody provide some insight as to why this happens and how I might be able to correct it (keep in mind that the DB was setup by a third party, so I cannot change too much of the underlying setup without possibly compromising their functionality).
I am trying to create an indexed view, but because I am using a MAX function, I get the error
Cannot create index on view "dbo.View" because it uses aggregate "MAX". Consider eliminating the aggregate, not indexing the view, or using alternate aggregates. For example, for AVG substitute SUM and COUNT_BIG, or for COUNT, substitute COUNT_BIG.
Am totally stuck on how I can replace the MAX function.
Any help would be appreciated.
SET ANSI_NULLS ON GO SET ANSI_PADDING ON GO SET ANSI_WARNINGS ON GO SET CONCAT_NULL_YIELDS_NULL ON GO SET NUMERIC_ROUNDABORT OFF GO SET QUOTED_IDENTIFIER ON GO SET ARITHABORT ON GO
CREATE VIEW [dbo].[View] WITH SCHEMABINDING AS
SELECT TOP 100 PERCENT MAX(js_id) AS job_event, job_id FROM dbo.JobEvent GROUP BY job_id ORDER BY job_event GO
CREATE UNIQUE CLUSTERED INDEX IX_VMaxJobEvent ON View (job_id)
Dear experts, I've been working for an ERP solutions, company, as a DBA....
we have around 1200 tables as wellas 650 views.....
we are not using clustered index on views..... using the clustered index will boost the performance? and the ERP is web based application. so that modifications will be done on a regular basis.... is it good thing to implement clustered indexes on these views....
please guide me in this regard
thank you verymuch
Vinod Even you learn 1%, Learn it with 100% confidence.
I had some issues yesterday with the fact that some of the tables I had indexed views for did not have a unique/clustered index. The tables had unique indexes and clustered indexes but not a unique/clustered index. What I was seeing were rows that should have been in the view, not showing up in a regular select but they would showup in a with noexpand hint.
To fix the problem I created a unique/clustered index on each of the underlying table but cannot find that requirement anywhere, is this a requirement and if so can someone tell me where to find it.
How do we defrag indexed views? Can any one give me a query to loop thru all the indexed views in the database and find out the fragmentation levels and also defrag them? Thanks in advance!
I have an indexed view with a clustered index on my database........when I try to run and update statement agaisnt the table that is referenced in the view, I get one of the following errors:
Lalitha writes "Can I use DML statements against indexed views? If yes how it works internally, means will the pages gets locked during update and inserts and when the base tables get reflected of these modified data?"
Each ProductGUID can and should have multiple records in the ProductPrice table. I want to create an indexed view that will group by ProductGUID that will show either the most recent custom price if a (isSRP = 'False') record exists or the most recent srp price if there is only (isSRP = 'True'), then a column stating whether the price column is taken from a (isSRP = 'True') record, and followed by the most recent srp price (isSRP = 'True').
SELECT [PP].ProductGUID AS [ProductGUID], CASE WHEN MIN(CASE [PP].IsSRP WHEN 'True' THEN 1 ELSE 0 END) = 0 THEN MAX(CASE [PP].IsSRP WHEN 'True' THEN 0 ELSE [PP].Price END) ELSE MAX([PP].Price) END AS [Price], MIN(CASE [PP].IsSRP WHEN 'True' THEN 1 ELSE 0 END) AS [PriceIsSRP], MAX(CASE [PP].IsSRP WHEN 'True' THEN [PP].Price ELSE 0 END) AS [SRP] FROM dbo.ProductPrice AS [PP] -- Eliminate all but the most recent custom price, and msrp price WHERE ([PP].IsSRP = 'True' AND [PP].EffectiveDate = (SELECT MAX(EffectiveDate) FROM dbo.ProductPrice AS innerPP WHERE innerPP.ProductGUID = [PP].ProductGUID AND innerPP.IsSRP = 'True')) OR ([PP].IsSRP = 'False' AND EffectiveDate = (SELECT MAX(EffectiveDate) FROM dbo.ProductPrice AS innerPP WHERE innerPP.ProductGUID = [PP].ProductGUID AND innerPP.IsSRP = 'False')) GROUP BY [PP].ProductGUID
This query works, but I can't create an indexed view on any query with a subquery. So, If I had some way of limiting the query to return only the most recent IsSRP = 'True' and the most recent IsSRP = 'False' (if one exists) without using a subquery then this would be aces.
Oh, and every ProductGUID has at least one IsSRP = 'True' record.
hi frends.i have such a great problem.i want to use union in indexedview and i must have to use it. because i cant make a one tablebecause in those two tables there are 2,000,000 records entereddaily.So please give me suggestion. can also give me alternate ofusing UNION in indexed view.and i want to use idexed view only becausei will do searching afterwards.Regards,Mr.MirzaSoftware Engineer.
Hi guys , we had data in tables for multiple users (Logins) .Each user data is identified by a one column named €œUSER€?. No user has direct access to tables and only through views .we have created views and stored proc .Views will perform DML operations on tables using condition WHERE USER=SUSER_SNAME() (i.e Logged in user).So no point of getting others user data.
Now the question is can I create indexed views?
If yes how can I implement .Because data depends on context is there any way to create global indexed views.
In case of indexed views query optimizer will automatically select indexed views for efficient way of execution .but I have to restrict to use only our existing views and these views have to refer indexed views and I need to force query optimizer not use indexed views.
We have a very huge database that stores 12 years of data(120 Million records). But our application mainly accesses past 3 years data i.e , the queries would scan the 120 million records even when it actually has to scan 30 million records alone (for 3 years).
Since few other important applications needs access to all the 12 years data, we are in a position to have 12 years data in the same database.
Right now we are looking for an approach that would help us to efficiently access the 3 years data alone and boost the performance.
1. Will SQL server table paritioning help in this scenario ?
Or
2. Indexed views would help us ? Is it possible to create indexed views based on year range and access the views in the stored procedures ?
Do not trust values returned by materialized views under SQL Serverwithout frequently checking underlying tables!!!I already posted this message under microsoft.public.sqlserver.serverand I'm amazed nobody from Microsoft answered about this problem. Byinserting lots of data into our two main tables for about 30 minutes,we can fail our materialized view that performs a count_big on thosetwo tables.Executing (after of course having stopped inserting rows in our twotables)[color=blue]> SELECT SUM(field1+field2+field3) FROM MatView option(expand views)[/color]DOES NOT RETURN the same value than:[color=blue]> SELECT SUM(field1+field2+field3) FROM MatView with (noexpand)[/color]The second call - using the materialized view - returns a smallernumber (as if counts were lost during our bulk insert)As our data has to be accurate, we cannot use Materialized viewsanymore. This problem does not occur when the amount of data insertedis smaller. Rebuilding the clustered index on the view fixes theproblem; do we have to constantly be rebuilding the index to keep theview synchronize !?!!?!Is there a way to tell that our view is not synchronized? Justcomparing values returned by our view does not work for us as data isconstantly been inserted.System: SQL server 2000 SP3 Enterprise EditionVincent LIDOU
With my understanding of indexed views and according to books I read"indexed views" are supposed to perform much better than "temp tables"(temp table having primary key and indexed view with clustered indexon the same keys).But when I tried in my system I am getting opposite results. WithIndexed Views it takes 3 times more time.Any body has any reasons for that? Or my understanding was wrong?thanksRaghu Avirneni
I have a table that I want to have a precalulcate length on a character fieldand group and sum up. Thought I could do this by creating a view with a groupby clause that includes the sum function. Unfortunately, the compilercomplains with:A clustered index cannot be created on the view 'MyView' because the indexkey includes columns which are not in the GROUP BY clause.Wish I could verbalize the problem a little better, but the following pareddown example should serve as a demonstration:SET ANSI_WARNINGS ONSET ANSI_PADDING ONSET ANSI_NULLS ONSET ARITHABORT ONSET CONCAT_NULL_YIELDS_NULL ONSET QUOTED_IDENTIFIER ONSET NUMERIC_ROUNDABORT OFFGOCREATE TABLE myTable(myID INT NOT NULL,RecNum INT NOT NULL,TestString VARCHAR(80) NOT NULL)GOINSERT INTO myTable VALUES(1, 1, 'a')INSERT INTO myTable VALUES(1, 2, 'ab')INSERT INTO myTable VALUES(2, 2, 'abc')GOCREATE VIEW dbo.MyView WITH SCHEMABINDING ASSELECTmyID = myID,slen = SUM(LEN(TestString)),recn = COUNT_BIG(*)FROM dbo.myTableGROUP BY myIDGOCREATE UNIQUE CLUSTERED INDEX IX_MyView ON MyView(myID, slen)-- A clustered index cannot be created on the view 'MyView' because-- the index key includes columns which are not in the GROUP BY clause.GODROP VIEW MyViewGODROP TABLE myTableGOThanks,Chris Rathman
I have a question regarding the locking behavior of indexed views. We have a 3rd party application and something like the following table:
CREATE TABLE [Person].[Person]( [BusinessEntityID] int NOT NULL, [FirstName] varchar(20) NOT NULL, [MiddleName] varchar(20) NULL,
[code]....
Also the 3rd party application uses an indexed view, which is based on the following query and has the same structure as the base table:
SELECT [BusinessEntityID], [FirstName], [MiddleName], [LastName], SUM([Quantity]) AS [SUMQuantity] FROM [Person].[Person] GROUP BY [BusinessEntityID], [FirstName], [MiddleName], [LastName]
The result is, that the indexed view has nearly the same data / entries as the base table. The indexed view is often queried like this:
SELECT SUM(SUMQuantity) FROM [vPerson] WITH(UPDLOCK, NOEXPAND) WHERE [BusinessEntityID] = 45 AND [FirstName] = 'test'
The base table is also queried very often with update locks (UPDLOCK). Because the indexed view is nearly just a copy of the base table and there is no performance gain (read), I would like to drop the indexed view. I'll then experience more locks / blocks, because now the queries are seperated on two objects.
Hi, I'm getting some unexpected behaviour from my SSIS packages when targeting tables that are being referenced by Indexed Views. There's two separate issues:
1. When writing into a pair of tables with a SuperType / SubType relationship concurrently with a pair of SS destinations I'm getting deadlocks between the two. Removing the index on the view that references both of these fixes the problem.
2. Much odder, I'm getting some extremely long waits (10 times longer than the whole package should take to run!) from an SS Destination adapter even when there's no data in the flow for it to bulk insert. Again, removing the indexed views that reference the destination table fixes the problem.
The views aren't mine, and (apparently) are required by the reporting app (BO), so removing them isn't really an option. I realise that there's quite a lot of overhead to maintaining indexed views, but unfortunately, the project is on a very tight timeline, so I can't look into it in as much detail as I'd like. I was wondering if anyone's experienced any similar issues, or would have any ideas as to where to start investigating?
I am having some questions on indexed views and aggregate tables.
My question is: To improve the performance of the queries, is it better to use indexted views or aggregates tables for those aggregates which are often queried?
I have problem that Im sure others must have had before so I am looking for advice on the best way to solve it. I have a table of text information tbl_base which is related to another table containing tags, which can contain several rows for each row in base.
I want to create an indexed view of the data for full text search. I would like to select all the tags related to a particular row in the tbl_base together into a string and join it to the end of the tbl_base table so they can be indexed along with the tbl_base data for full text indexing. Ive tried several methods but I am never able to make an index on my view because it say I cant use COALESCE, or Cursors.
Sample data here :
tbl_base
id | Text ------------------------ 1 | BLah blah 2 | Dum de dum 3 | HAr HAr
tbl_base_tags
tagID | base_id | TagText -------------------------- 1 | 1 | first 2 | 1 | second 3 | 1 | third 4 | 2 | fourth
The view I want to end up with will look like this :
vw_tables
base_id | Text | Tags ------------------------------------- 1 | Blah blah | first second third 2 | dum de dum | fourth
How can I achieve this? Do I have to index all the tables seperately?
Hi, I have a problem, maybe someone can help me.I'm traing to create a view with a Linked ServerThis query works great:select id, descrfrom SERVER.DB.dbo.TABLEWhen I tray to create the view:CREATE VIEW dbo.View1 WITH SCHEMABINDINGASselect id, descrfrom SERVER.DB.dbo.TABLEGOI have this error:Server: Msg 4512, Level 16, State 3, Procedure Pais2, Line 3Cannot schema bind view 'dbo.View1' because name 'SERVER.DB.dbo.TABLE'is invalid for schema binding. Names must be in two-part format and anobject cannot reference itself.So I try this:CREATE VIEW dbo.View1 WITH SCHEMABINDINGASselect SERVER.DB.dbo.TABLE.id, SERVER.DB.dbo.TABLE.descrfrom SERVER.DB.dbo.TABLEGOI have this error:Server: Msg 117, Level 15, State 2, Procedure Pais2, Line 3The number name 'SERVER.DB.dbo.TABLE' contains more than the maximumnumber of prefixes. The maximum is 3.Then I try this:CREATE VIEW dbo.View1 WITH SCHEMABINDINGASselect a.id, a.descrfrom SERVER.DB.dbo.TABLE as AGOI Have this errorServer: Msg 4512, Level 16, State 3, Procedure View1, Line 3Cannot schema bind view 'dbo.View1' because name'iservsql1.osderrhh.dbo.pais' is invalid for schema binding. Namesmust be in two-part format and an object cannot reference itself.This query alone works great:select a.id, a.descrfrom SERVER.DB.dbo.TABLE as AThe names aren't what I describe here (id is not valid without []).ANY IDEAS?!??!?!I don't know what else can I do.I need help!!!TANKS A LOT!!!!!!!!
In the SQL Server 2014 Management Studio's object explorer indexed views with schemabinding don't have an index node. Thus, you can create and drop Indexes for views only via T-SQL. The SQL Server Management Studio 2012 still shows the index node.
Is there some Management Studio setting in version 12.0.2000.8 which I am missing?
when i do a snapshot i have it set up to truncate before inserting. As a result I'm getting an error saying that it cant truncate a table reference in an indexed view. What settings should i use to allow for a snapshot in this instance? Should i manually drop the databinding then snap then recreate the databinding? there has to be a better way
When I change a table through the Enterprise Manager, I then have to go and manually refresh all views dependant on that table, even though they don't reference the new column explicitly (they use .*) - just opening the view, typing a space and resaving it works. Obviously this is the dumb way to do it - is there a way to automatically refresh the views?
I have created a table from another table where I specified that one of the fields, an number field, is sorted in ascending order and have NOT specified that it is to be an indexed field and there are 10 million records, from 1 to 10,000,000 exactly.
Now, if I query that table, asking to return records 1-1,000 from that non indexed number field that I sorted in ascending order (where number field <= 1,000) , will it run as fast as if it were indexed?
In other words, does SQL know somehow that these records are sorted in ascending order and so will not do a full table scan, stopping at 1,000 to return my data set?
Or is there no way for SQL to know this and only specifying an indexed field allows SQL to know that its in some order and so it doesn't have to do the full scan?
This is a general question regarding the use of view and storedprocedures. I'm fairly new to databases and SQL.I've created a SQL database using an Access Data Project ("ADP") andI'm satified with the table structure. I've moved on to building somefront ends for our users.I'm running into situations where I want subreports to be built fromqueries [views or stored procedures-I don't know which to use so I usethe term query] that are dependent on the values in other controls.I've played with stored procedures and I've figured out how to sendcriteria to a stored procedure and then dynamically change the recordsource of a subreport.However, I'm running into cases where I can't add records to theresults of a stored procedure. The table I'm running a stored procedureon has five fields: (1) Primary Key for each record, (2) FundID that'sa primary key in another table, (3) CompanyID that's a primary key inanother table, (4) Attribute 1 of the (Fund/Company) and (5) Attribute2 of the (Fund/Company).The stored procedure filters the set of Fund/Companies based on aFundID from a form. I can update this stored procedure. However, forusers, they would like to see the Fund Name from the table that hasunique FundIDs. As soon as I include that into the stored procedure, Ican no longer add records.My questions are many:1. Is there a primer online that discusses the theory behind myquestion? Recordsets, updatability, working with recordsets in forms?2. What are some best practices for developing subreports, combo boxes,list boxes, etc. where the data is dependent on the values in a control3. I'm struggling with the best ways to grab objects on a form. If I'mon the main form I'm comfortable working with theMe.__object__.__sub-oject routine. However, if I'm in one subform whereI need another subform to change based on the record I'm in, I feelthat my code to get at the subform is very klunky..forms.main form name.sub form name.form.record sourceI don't even know how I figured out the "form" part before recordsource. Again, are there some basic rules or guides about navigatingthrough forms in VBA?4. Should I be developing front ends in some other environment?I know it's a lot, but all the advice from the newsgroups seems topresuppose some knowledge about how ADP, ADO, ODBC..blah blah and Ican't seem to find any documents about ADP and SQL.
My database's design is set out here. In summary, I'm trying to model a Stock Exchange for a Technical Analysis application written using Visual C++. In order to create the hierachy I'm using a Nested Set Model. I'm now trying to write code to add and delete equities (or, more generically, nodes) to the database using a form presented to the user in my application. I have example SQL code to create the necessary add and delete procedures that calculate the changes to the values in the lft and rgt columns, but these examples focus around a single table, where as my design aggregates rows from multiple tables using UNION ALL:
Code Snippet CREATE VIEW vw_NSM_DBHierarchy -- Nested Set Model Database Hierarchy AS SELECT clmStockExchange, clmLeft, clmRight FROM tblStockExchange_ UNION ALL SELECT clmMarkets, clmLeft, clmRight FROM tblMarkets_ UNION ALL SELECT clmSectors, clmLeft, clmRight FROM tblSectors_ UNION ALL SELECT clmEPIC, clmLeft, clmRight FROM tblEquities_
Essentially, I'm trying to create an updateable view but I receive the error "UNION ALL View is not updatable because a partitioning column was not found". I suspect that my design in wrong or lacks and this problem is highlighting the design flaws so any suggestions would be greatly appreciated.
Fellow database developers,I would like to draw on your experience with views. I have a databasethat includes many views. Sometimes, views contains other views, andthose views in turn may contain views. In fact, I have some views inmy database that are a product of nested views of up to 6 levels deep!The reason we did this was.1. Object-oriented in nature. Makes it easy to work with them.2. Changing an underlying view (adding new fields, removing etc),automatically the higher up views inherit this new information. Thismake maintenance very easy.3. These nested views are only ever used for the reporting side of ourapplication, not for the day-to-day database use by the application.We use Crystal Reports and Crystal is smart enough (can't believe Ijust said that about Crystal) to only pull back the fields that arebeing accessed by the report. In other words, Crystal will issue aSelect field1, field2, field3 from ReportingView Where .... eventhough "ReportingView" contains a long list of fields.Problems I can see.1. Parent views generally use "Select * From childview". This meansthat we have to execute a "sp_refreshview" command against all viewswhenever child views are altered.2. Parent views return a lot of information that isn't necessarilyused.3. Makes it harder to track down exactly where the information iscoming from. You have to drill right through to the child view to seethe raw table joins etc.Does anyone have any comments on this database design? I would love tohear your opinions and tales from the trenches.Best regards,Rod.
