Views Vs Functions
Aug 22, 2007I wanna know which adventages and disadventages have the command create funtion over create view or if you know a link that explain that
View 7 RepliesI wanna know which adventages and disadventages have the command create funtion over create view or if you know a link that explain that
View 7 RepliesI have a view that contains a complex query. A few of the columnscall a function that returns a specific output. I also use a functionto do a join as well.For example:SELECT l.ID, dbo.getStatus(l.ID) AS statusIDFROM tableName ALEFT OUTER JOIN dbo.Status_LKP s ON dbo.getStatus(l.Leg_ID) =s.statusIDFor 800 records, this query takes about 9 seconds. I realize that foreach record, the function is executed on a per row basis, so I amlooking for alternatives.Does anyone know of other ways to accomplish something of the same?Basically I would like to include UDFs in a query and use those UDFsin the where and join clauses.Thanks
View 2 Replies View RelatedHi all,As all of you are aware you can Encrypt your Triggers/Stored Procedures/Views And Functionsin Sql Server with "WITH ENCRYPTION" clause.recently i came across a Stored procedure on the Net that could reverse and decrypt all Encrypted objects.i personally tested it and it really works.That's fine (of course for some body)Now i want to know is it a Known Bug for Sql Server 2000 and is there a permanent solution for Encrypting mentioned objects.Thanks in advance.Best Regards.
View 2 Replies View RelatedHi I am writting Stored Procedures that have to be built on the base of other tables specially created for this purpose, is it better to create these intermediate tables as views or as functions returning tables? I guess views would be lighter on performance as they would not be created on the fly?
View 2 Replies View RelatedAre there any disadvantages in respect to performance in using table valued functions instead of using a view.
Thanks...
Hi All,
Novice question. Would someone explain tell me what a view is used for? Also I am confused about the difference between a function and a stored procedure. They both seem like functions to me.
Hello:
Is it possible to standardize sql views or functions to filter data for the user, before they view the report? For example if I have a SQL view that filters for "green, cotton-made socks", can this somehow be an option among others before a user presses "view report?"
A response is greatly appreciated. If this is possible, how ?
Many thanks.
Hi,
What is the basic difference between
store procedure, Functions and views
Thanks
I am working in a project where the business model is complex enoughthat many common retrieval functions become difficult to develop andmaintain in single query statements or functions.I have found the logic is easier to implement (and later modify whenthe code is no longer freshly remembered), by implementing theprocessing layers in nested views, and functions that callsub-functions (UDFs), not too unlike object based programming ornon-DBMS procedural languages. In some cases, the views and functionsare nested three deep.So far, from a design standpoint, this practice is working very well.Code that would be a recusive mess is reduced to two or three simplercode blocks. With the proper indexing and query structure, performanceseems to be satisfactory (time will tell).In MS SQL Server, is there anything which makes this practice unsound?Examples:CREATE VIEW vw2 AS SELECT * FROM tbl1 WHERE ...CREATE VIEW vw3 AS SELECT * FROM vw2 WHERE ...Application uses: SELECT * FROM vw3-or-CREATE FUNCTION udf2 AS SELECT * FROM tbl1 WHERE ...CREATE FUNCTION udf3 AS SELECT * FROM udf2 WHERE ...Application uses: SELECT udf3(param) AS value
View 5 Replies View RelatedI was wondering if it was possible to incorporate sql views or functions that filter data on the top bar for users when they run a report.
a response is greatly appreciated! If so, how?
Hi,Right, i have a fairly good understanding of SQL. However, i have a fairly basic understanding of SQL Server.I know Storedprocedures are really good and i'm starting to use them. I understand they are good for making inserting, updating very easy.However when you look at a SQL Server database you get various folder, this leaves me a little confused with what they are all used for? whats the difference between these?Thanks in advance!sorry for the basic question, i'll try to challange you next time
View 1 Replies View RelatedYes, I do know what this means and why the error is thrown but this is not my question.
I have two servers that are both running Windows Server 2003 and SQL Server 200 SP3. Below are the results from both servers using @@version
Sever 1 (BB)
Microsoft SQL Server 2000 - 8.00.760 (Intel X86)
Dec 17 2002 14:22:05
Copyright (c) 1988-2003 Microsoft Corporation
Developer Edition on Windows NT 5.2 (Build 3790: Service Pack 1)
Server 2 (Genesis)
Microsoft SQL Server 2000 - 8.00.760 (Intel X86)
Dec 17 2002 14:22:05
Copyright (c) 1988-2003 Microsoft Corporation
Developer Edition on Windows NT 5.2 (Build 3790: Service Pack 1)
These servers are identical or so it seems. I've got a real ugly query that uses views and a derived table to get results. The problem is the 256 limit message only comes up on one server and on the other (Genesis) the query runs fine. I get the error though it reads a 260 limit on a box with SP4 applied. I've also run the query on a box that is Windows 2003, sql2k and sp4 and the query runs but not on a similar server here. This is all very odd. Please note that the database structure, views, etc are all exactly the same as far as I know.
Any suggestions? There seems to be no pattern between versions of Windows and/or SP levels.
Greetings,
We have recently begun using transactional replication to keep the data in our SQL Servers synchronized in a geographically dispersed environment. We replicate our tables but we have never replicated views, stored procedures, or user functions in our production systems. We are thinking of doing so but wonder if the overhead of running the replication agents doesn't outweigh the benefits of having replication assist with the occassional change to these design elements.
Is anyone on this forum replicating views, sprocs, and user functions? What has your experience been?
Thanks for any ideas that you share.
BCB
I developed a search stored proc that searches all orsome of Procs, Views, Triggers and functions. Would anyone be interestedto see it posted here?Do you have any suggestions about other places, websites forums ...., toshare something I have developed?Thanks you for your response in advancePLease send me emailJoin Bytes! {Remove ### before responding}
View 1 Replies View Related
Hi Folks,
I am writing a program that transforms a generic MS SQL database to make it compatible with our application. In order to make the transformation, I have to access all the elements of the generic database programmatically.
I know that the Master database contains all this information. Is there a query that allows me to access the "non-system" tables, sps, views, and functions?
For Tables, I need to know the Name(s) of the tables, the column names, the column type, ALLOW Nulls, Primary Key, Identity Seed settings, and Triggers.
For SPs, I need to know the Name(s) and access the SP source code (assuming it's unencrypted).
For Views, I need to know the Name(s) and access the Views Source
For functions, I need to know the Name(s) and access the function source.
I can see various tables in the Master database from management studio, like sys.objects, sys.tables - which look like they have the info I need. However, when I run a query against master like:
select * from sys.objects .. I get an error:
Msg 208, Level 16, State 1, Line 1
Invalid object name 'sys.objects'.
Thank you in advance.
I am creating mateialized view but it is failing with error that it can't be schema bound.
The query I am working to create materialized view are having joins with different tables and function.
Is it possible to create Indexed views on user defined functions?
The data I am pulling is correct I just cant figure out how to order by the last 8 numbers that is my NUMBER column. I tried adding FOR XML AUTO to my last line in my query: From AP_DETAIL_REG where AP_BATCH_ID = 1212 and NUMBER is not null order by NUMBER FOR XML AUTO) as Temp(DATA) where DATA is not null
but no change same error.
Output:
1234567890000043321092513 00050020
Select DATA from(
select '12345678'+
left( '0', 10-len(cast ( CONVERT(int,( INV_AMT *100)) as varchar))) +
cast (CONVERT(int,(INV_AMT*100)) as varchar) +
left('0',2-len(CAST (MONTH(DATE) as varchar(2))))+
CAST (MONTH(DATE) as varchar(2)) +
left('0',2-len(CAST (day(CHECK_DATE) as varchar(2)))) +
CAST (day(DATE) as varchar(2))+right(cast
(year(DATE)
[code]....
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.
View 15 Replies View RelatedI was playing around with the new SQL 2005 CLR functionality andremembered this discussion that I had with Erland Sommarskog concerningperformance of scalar UDFs some time ago (See "Calling sp_oa* infunction" in this newsgroup). In that discussion, Erland made thefollowing comment about UDFs in SQL 2005:[color=blue][color=green]>>The good news is that in SQL 2005, Microsoft has addressed several of[/color][/color]these issues, and the cost of a UDF is not as severe there. In fact fora complex expression, a UDF in written a CLR language may be fasterthanthe corresponding expression using built-in T-SQL functions.<<I thought the I would put this to the test using some of the same SQLas before, but adding a simple scalar CLR UDF into the mix. The testinvolved querying a simple table with about 300,000 rows. Thescenarios are as follows:(A) Use a simple CASE function to calculate a column(B) Use a simple CASE function to calculate a column and as a criterionin the WHERE clause(C) Use a scalar UDF to calculate a column(D) Use a scalar UDF to calculate a column and as a criterion in theWHERE clause(E) Use a scalar CLR UDF to calculate a column(F) Use a scalar CLR UDF to calculate a column and as a criterion inthe WHERE clauseA sample of the results is as follows (time in milliseconds):(295310 row(s) affected)A: 1563(150003 row(s) affected)B: 906(295310 row(s) affected)C: 2703(150003 row(s) affected)D: 2533(295310 row(s) affected)E: 2060(150003 row(s) affected)F: 2190The scalar CLR UDF function was significantly faster than the classicscalar UDF, even for this very simple function. Perhaps a more complexfunction would have shown even a greater difference. Based on this, Imust conclude that Erland was right. Of course, it's still faster tostick with basic built-in functions like CASE.In another test, I decided to run some queries to compare built-inaggregates vs. a couple of simple CLR aggregates as follows:(G) Calculate averages by group using the built-in AVG aggregate(H) Calculate averages by group using a CLR aggregate that similatesthe built-in AVG aggregate(I) Calculate a "trimmed" average by group (average excluding highestand lowest values) using built-in aggregates(J) Calculate a "trimmed" average by group using a CLR aggregatespecially designed for this purposeA sample of the results is as follows (time in milliseconds):(59 row(s) affected)G: 313(59 row(s) affected)H: 890(59 row(s) affected)I: 216(59 row(s) affected)J: 846It seems that the CLR aggregates came with a significant performancepenalty over the built-in aggregates. Perhaps they would pay off if Iwere attempting a very complex type of aggregation. However, at thispoint I'm going to shy away from using these unless I can't find a wayto do the calculation with standard SQL.In a way, I'm happy that basic SQL still seems to be the fastest way toget things done. With the addition of the new CLR functionality, Isuspect that MS may be giving us developers enough rope to comfortablyhang ourselves if we're not careful.Bill E.Hollywood, FL------------------------------------------------------------------------- table TestAssignment, about 300,000 rowsCREATE TABLE [dbo].[TestAssignment]([TestAssignmentID] [int] NOT NULL,[ProductID] [int] NULL,[PercentPassed] [int] NULL,CONSTRAINT [PK_TestAssignment] PRIMARY KEY CLUSTERED([TestAssignmentID] ASC)--Scalar UDF in SQLCREATE FUNCTION [dbo].[fnIsEven](@intValue int)RETURNS bitASBEGINDeclare @bitReturnValue bitIf @intValue % 2 = 0Set @bitReturnValue=1ElseSet @bitReturnValue=0RETURN @bitReturnValueEND--Scalar CLR UDF/*using System;using System.Data;using System.Data.SqlClient;using System.Data.SqlTypes;using Microsoft.SqlServer.Server;public partial class UserDefinedFunctions{[Microsoft.SqlServer.Server.SqlFunction(IsDetermini stic=true,IsPrecise=true)]public static SqlBoolean IsEven(SqlInt32 value){if(value % 2 == 0){return true;}else{return false;}}};*/--Test #1--Scenario A - Query with calculated column--SELECT TestAssignmentID,CASE WHEN TestAssignmentID % 2=0 THEN 1 ELSE 0 END ASCalcColumnFROM TestAssignment--Scenario B - Query with calculated column as criterion--SELECT TestAssignmentID,CASE WHEN TestAssignmentID % 2=0 THEN 1 ELSE 0 END ASCalcColumnFROM TestAssignmentWHERE CASE WHEN TestAssignmentID % 2=0 THEN 1 ELSE 0 END=1--Scenario C - Query using scalar UDF--SELECT TestAssignmentID,dbo.fnIsEven(TestAssignmentID) AS CalcColumnFROM TestAssignment--Scenario D - Query using scalar UDF as crierion--SELECT TestAssignmentID,dbo.fnIsEven(TestAssignmentID) AS CalcColumnFROM TestAssignmentWHERE dbo.fnIsEven(TestAssignmentID)=1--Scenario E - Query using CLR scalar UDF--SELECT TestAssignmentID,dbo.fnIsEven_CLR(TestAssignmentID) AS CalcColumnFROM TestAssignment--Scenario F - Query using CLR scalar UDF as crierion--SELECT TestAssignmentID,dbo.fnIsEven_CLR(TestAssignmentID) AS CalcColumnFROM TestAssignmentWHERE dbo.fnIsEven(TestAssignmentID)=1--CLR Aggregate functions/*using System;using System.Data;using System.Data.SqlClient;using System.Data.SqlTypes;using Microsoft.SqlServer.Server;[Serializable][Microsoft.SqlServer.Server.SqlUserDefinedAggregate (Format.Native)]public struct Avg{public void Init(){this.numValues = 0;this.totalValue = 0;}public void Accumulate(SqlDouble Value){if (!Value.IsNull){this.numValues++;this.totalValue += Value;}}public void Merge(Avg Group){if (Group.numValues > 0){this.numValues += Group.numValues;this.totalValue += Group.totalValue;}}public SqlDouble Terminate(){if (numValues == 0){return SqlDouble.Null;}else{return (this.totalValue / this.numValues);}}// private accumulatorsprivate int numValues;private SqlDouble totalValue;}[Serializable][Microsoft.SqlServer.Server.SqlUserDefinedAggregate (Format.Native)]public struct TrimmedAvg{public void Init(){this.numValues = 0;this.totalValue = 0;this.minValue = SqlDouble.MaxValue;this.maxValue = SqlDouble.MinValue;}public void Accumulate(SqlDouble Value){if (!Value.IsNull){this.numValues++;this.totalValue += Value;if (Value < this.minValue)this.minValue = Value;if (Value > this.maxValue)this.maxValue = Value;}}public void Merge(TrimmedAvg Group){if (Group.numValues > 0){this.numValues += Group.numValues;this.totalValue += Group.totalValue;if (Group.minValue < this.minValue)this.minValue = Group.minValue;if (Group.maxValue > this.maxValue)this.maxValue = Group.maxValue;}}public SqlDouble Terminate(){if (this.numValues < 3)return SqlDouble.Null;else{this.numValues -= 2;this.totalValue -= this.minValue;this.totalValue -= this.maxValue;return (this.totalValue / this.numValues);}}// private accumulatorsprivate int numValues;private SqlDouble totalValue;private SqlDouble minValue;private SqlDouble maxValue;}*/--Test #2--Scenario G - Average Query using built-in aggregate--SELECT ProductID, Avg(Cast(PercentPassed AS float))FROM TestAssignmentGROUP BY ProductIDORDER BY ProductID--Scenario H - Average Query using CLR aggregate--SELECT ProductID, dbo.Avg_CLR(Cast(PercentPassed AS float)) AS AverageFROM TestAssignmentGROUP BY ProductIDORDER BY ProductID--Scenario I - Trimmed Average Query using built in aggregates/setoperations--SELECT A.ProductID,CaseWhen B.CountValues<3 Then NullElse Cast(A.Total-B.MaxValue-B.MinValue ASfloat)/Cast(B.CountValues-2 As float)End AS AverageFROM(SELECT ProductID, Sum(PercentPassed) AS TotalFROM TestAssignmentGROUP BY ProductID) ALEFT JOIN(SELECT ProductID,Max(PercentPassed) AS MaxValue,Min(PercentPassed) AS MinValue,Count(*) AS CountValuesFROM TestAssignmentWHERE PercentPassed Is Not NullGROUP BY ProductID) BON A.ProductID=B.ProductIDORDER BY A.ProductID--Scenario J - Trimmed Average Query using CLR aggregate--SELECT ProductID, dbo.TrimmedAvg_CLR(Cast(PercentPassed AS real)) ASAverageFROM TestAssignmentGROUP BY ProductIDORDER BY ProductID
View 9 Replies View RelatedWhich is more efficient? One large view that joins >=10 tables, or a few smaller views that join only the tables needed for individual pages?
View 1 Replies View RelatedHello.
Newbie here. I've only been using SQL for about a year now and have some minor questions about sql objects that reference other objects.
We have some views which reference other views in the joins. I will call one the primary view and the one being referenced in the joins as the secondary view.
Recently we made changes to the secondary view.
After which the primary views which referenced it would not work because of this change and had to be 'refreshed' by using drop/create scripts which essentially just dropped it and recreated the exact same view. I do not recall the exact error message that was returned other than it seemed to suggest that it could no longer see the secondary view since it had been changed. Nothing in the primary view was changed in any way, just the secondary.
Some here where I work have suggested off hand that this was a recompile of the primary view because the contents of the secondary changed.
My questions are:
1. Exactly why did this happen and is there a proper name for it when it does?
2. The same problem does not seem to occur when we have stored procedures referencing views in the joins which had just been changed. Why is that?
Thanks for any help on the matter. I greatly appreciate it.
Hello,
to make a report easier I'm developing it using a view of joined views of joined views.
Is there any significant performance penalty as opposed to just having one big select?
Cheers.
Hello There,I'm trying to create a view that has calculations dependent oncalculations, where the problem resides is that each time I make acalculation I must create an intermediate view so I can reference aprevious calculation.for example lets say I have my_table that has columns a & b. now I wanta view that has a & b, c = a + b, and d = c + 1.this is grossly simplified, the calculations I actually use are fairlycomplex and copying / pasting them is out of the question.so what I have is my_view_a which makes column c, and my my_view_finalwhich makes column d (however, in my real application I have 5 of theseviews, a/b/c/d/e/)is there anyway I can consolidate all these views into one? I wasthinking of using a stored procedure with temp tables or somethingalong those lines.I just which I can use the aliases that I create for c in d in onestep.any insight would be greatly appreciated.
View 5 Replies View RelatedGuys I need help with sql server 2005 syntax
My goal is up update a table called UserStats.
I have numerous functions in SQL that return Scalars (one for each statistics I want to use)
How do I then use a stored proceedure to return a table of the values for use on my site?
WIthin SQL Server 2005, there are functions. This feature is new to me and I haven't found anyone that has written their own fucntions? I'm wondering if functions are written the same as stored procedures, and can a function be called from a stored procedure or even from within a query.
hello Im having a difficult time translating this query from Access to SQL because it uses the First/Last functions.
I have a 'Projects' Table and a 'Project_Comments' table, each has a 'Project_ID' field which links the 2 together. What I need to do is retrieve a Project List from the Projects Table and also the first Comment of each project based on the Commend_date field in the Project_Comments table. This is the MS ACCESS query:
SELECT Projects.Project_Number, Projects.Project_Name, First(Project Comments.Comment_Date), First(Project_Comments.Notes)
FROM Projects Left Join Projec_Comments ON
Projects.Project_Number = Project_Comments.Project_Number
GROUP BY Projects.Project_Number, Projects.Project_Name
Now I can use Min() for the Date instead of First, however I dont know what to do with the Notes field. Any help on how to get this over to sql would be greatly appreciated!
Hi,
I have created a function that returns a comma seperated list of product id's from a table. I need to call this function from a stored procedure to help filter my product results, something like the following:
SET @SQL = 'SELECT dbo.Products.ProductID FROM dbo.Products WHERE dbo.Products.ProductID IN (' + dbo.GetModels('dbo.Products.ProductID', '') + '))'
The problem I am having when executing the above is:
"Conversion failed when converting the varchar value 'dbo.Products.ProductID' to data type int."
Can anyone shed some light on how I can call the function, feeding through the product ID from the row of the select statement I am trying to execute (if this makes sense).
Any help would be great.
Matt
Iam trying to convert a date string to date format.....in access I could just use CDate, but SQL apparently does not allow this.
Any help appreciated
Thanks
Hello,how I can use a function of my own within a select statement. I triedcreate function funny() returns intas beginreturn( 2 )end goand then "select funny()" but 'funny' is not a recognized function name.How can I solve this?thanks and regardsMark
View 1 Replies View RelatedHi,,I'm having a problem with calling a function from an activex scriptwithin a data transformation. the function takes 6 inputs and returnsa single output. My problem is that after trying all of the stuff onBOL I still can't get it to work. It's on the same database and I'mrunning sql 2000.when I try to call it I get an error message saying "object requiredfunctionname" If I put dbo in front of it I get "object required dbo".Can anyone shed any light on how i call this function and assign theoutput value returned to a variable name.thanks.
View 7 Replies View RelatedHello,
I've created a function that performs modulo. I understand that SQL server 2000 / 2005 uses % for modulo, but we have an application that was written for Oracle. Oracle has a mod(dividend, divisor) function.
As to not rewite the queries, I would like to implement the function below:
the function executes properly but I must prefix it with the dbo schema.
Net: I can execute --- select dbo.mod(9,2) and it returns a 1 just like it should.
but I can not execute --- select mod(9,2) I receive the error "'mod' is not a recognized function name." on SQL 2000 and 2005.
If I can execute select mod(9,2) then I won't need to re-write any queries.
Also, on SQL 2005, I have tried to adjust the default shema, and the execute as clause, but neither helped my cause.
I'm going to try building the function in the CLR, but I think I will be faced with the same problem.
Can someone point me in the right direction?
Thanks
Tom
create function mod
(
@dividend int,
@divisor int
)
RETURNS int
as
begin
declare @mod int
select @mod = @dividend % @divisor
return @mod
end
Hi,
I have to calculate data in function with "EXEC". During runtime I get the Error:
"Only functions and extended stored procedures can be executed from within a function."
I would use a Stored Procedure, but the function is to be called from a view. I don't understand, why that should not be possible. Is there any way to shut that message down or to work around?
btw: Storing all the data in a table, would mean a lot of work, I rather not like to do. ;-)
Thx for any help
Blubb10
I just installed SSRS 2005 and I have experience with SQL.
How come this function does not work?
SELECT SUBSTRING(YEAR_MONTH, 1, 2) AS Expr1
FROM table1
I get a message which states that this command is not supported by the provider?
It works fine with other SQL tools like winsql?
thanks