I'm moving some queries out of an Access front end and creating views out of
them in SQL Server 2005 express. In some of the numeric fields, I use nz
quite often, ( i.e. nz([MyField],0)) to return a zero if the field is null.
Is there anything equivalent to this in SQL Server? Right now I'm using
CASE WHEN ... but it seems like an awful lot of script to write just to
replace null with a zero.
I 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
Recently I changed over a ASP script from our old Access 97 database to our new SQL database. When I changed it over, some of my SQL pulls on my Active Server Page started to give me erros. One of them is the function date(). When I used it pulling from Access like this :
strSQLQ = "SELECT * FROM cocoitem WHERE CustNum = '" & strcustnum & "' AND stat = 'C' AND [due-date] > DateAdd('yyyy', -1, Date()) Order By [cust-po], [due-date] ASC ;"
Then it worked fine. When I redirected the ASP to the new SQL server I recieved an error like this:
Microsoft OLE DB Provider for SQL Server error '80040e14'
'Date' is not a recognized function name.
/scripts/order/shippingstatsclose.asp, line 45
So my question is, what is the SQL server equivalent of the function Date()?
Hi I have a problem which I’m not sure how to resolve! I have a aspx with two drop down list; 1st one has (annual salary, daily salary, hourly rate) 2nd one has ( 0-4999, 5000-9999......)
The second one is generated by the value selected in the first one. I have stored the values in a table (as nvarchar) and used sqldatasource to run a query, which matches the entry in the first box and fill the second drop down list accordingly.
How ever I have a problem, when I want some one to search for example; an average salary of 5000-9999, it should output entry's that have a similar daily rate, and hourly rate... But I’m not sure how I can accomplish this, does any one have any ideas! Many thanks
Hi,the Soundex search words that sounds similar.Does MS SQL Server has some function to make some intuitive search?For example, for search term database, it should return rows that contains: "database" word, but also rows that contains "Oracle", "MySQL", "MS SQL" etc. terms.
Can someone tell me if this is a SQL Server bug? I tried this in both version 7 and 2000, the results are the same.
DECLARE @timeA DATETIME DECLARE @timeB DATETIME DECLARE @msDiff INT
SET @timeA = GETDATE() SET @msDiff = 0
WHILE @msDiff <= 10 BEGIN SET @timeB = DATEADD(ms,@msDiff,@timeA) PRINT 'If adding ' + CONVERT(VARCHAR,@msDiff) + ' milliseconds to Time B, then Time B is ' + CONVERT(VARCHAR,DATEDIFF(ms,@timeA,@timeB)) + ' millisecond greater than Time A' SET @msDiff = @msDiff + 1 END
This seems like a serious bug if an application depends heavily on milliseconds comparison.
I am sorry to continue bothering this forum with the continuation of this question but here it is. And thank you to Craig for giving me the equivalent of the function Date() in SQL. Now when I pull from the SQl Server with the old ASP pull with this statement using GETDATE()
strSQLQuery1 = "SELECT * FROM cocoitem WHERE CustNum = '" & strcustnum & "' AND (stat = 'O' OR stat = 'F') AND [due-date] > DateAdd('yyyy', -1, GETDATE()) Order By [cust-item], [due-date] ASC;"
I get this: Microsoft OLE DB Provider for SQL Server error '80040e14'
Invalid parameter 1 specified for dateadd.
/scripts/order/shippingstatsopen.asp, line 28
So I guess I need to also know the equivalent of DateAdd . Also, does anyone know of a Access Function to Sql 7 function comparison chart so I can write for the new database comprehendingly?
I am new to this, SQL Server. I hv worked in Oracle. Now I am learning 'SQL Server'. In Oracle, it has features like Packages and functions (PL/SQL), like that in SQL Server, is there any facility available?.
Hi, I am still learning the bells and whistles of SQL Server and was wondering if I can find out the query that caused my trigger to fire, so that I can log this in another audit table. I have an If Update ( My_Column ) trigger set up, where once an update happens to My_Column much information from the updated row along with , Host_Name and App_Name is sent. I also want to send the exact query used to update it, any ideas? Any comments, suggestions will be greatly appreciated. Thanks, Kartik
I would like to know how to write a function that will go through datain a column and change it. For example, I have a column of ISBN's forbooks, and the ISBN's have a period in them randomly distributed. I'dlike to pull the period out.Any help I can get will be appriciated.Thanks,Bill
Hi,Do any versions of SQL Server support the following functions, asthey appear in the Oracle Database:-1) XMLElement2) XMLAttributes3) XMLForestThanks in Advance for your replyByeAmardeep Verma
Does anyone have financial functions to be run in SQL Server 2000? For example, future value, interest rate, payments, and so on. Or where can I find them on Internet?
I'm upsizing MS-Access to SQL Server 2005. I need to convert the following functions: TRANSFORM PIVOT FORMAT MID
Are there any similar functions in SQL Server?
Also I have a query as follows:
SELECT Mid$([AccountNumber],3,8) AS [Account#], Format([checkamount]*100,"000000000") AS Amount, IIf(IsNull([statusdate])," ",Format([statusdate],"yyyymmdd")) AS [Date] FROM tblResult;
I want to replace my Windows 2000 SQL Server 2000 with a new beefier machine. And I really don't want to change all the setups on the users PCs to point to this new machine. So, I want the new machine to have the same name as the old machine. I think that Windows actually uses SIDs and not the name so I'm wondering what problems I may cause by just naming the new machine the same as the old and replacing?
My guess is that this is done everyday. Does anyone know where I can find information on how to do this safely?
I have 3 fields in my table say (F1, F2, F3). I want to get the max value out of the three fields for each row. I can create a user-defined function which accepts 3 arguments and then return the max value if i am using SQL Server 2000. But now i am using only SQL Server 7.0 (it does not support user-defined functions :confused: )
So any one could kindly let me know how could i do it in SQL Server 7.0
Hi, I saw in some websites that there are functions freeze and thaw in SQL server.I want to freeze the SQL server for some time and then use the thaw to unfreeze.I want to know how it could be done in SQL server 2005
Hi all!!Does anybody know how I can create a function in SQL 7.0?? I have tocreate functions that return a value that can be used in a selectstatement. I think SQL Server version 7.0 doesn't support CREATEFUNCTION, does it?Ex:Select MyFunction(Parameter)From MyTableThanks a lot,
Hi , I have a question about calling functions in SQl Server 2005.
Let's say that I have created as a dbo a function called Calculations.
If I want to call it from T-SQL I will write Select dbo.Calculations (arguments if any) etc.
My question is If I can skip the "dbo" part. Call the function without using the dbo . Can I do that ? Should I create the function as supervisor ? Does Sql Server has a property or something which will allow me to call the function without using the "dbo." ?
I found a search-and-replace program for SQL server that works GREAT, but I have a list of about 200 words to search for, with corresponding replacements. Rather than editing the code below for *each* word and running it 200 separate times, I'd like to iterate through the list, but my MS-SQL programming skills are...light (to say the least). Anyone have any ideas how I can create a list or hash-type variable and use the code to loop through and do the replacements all at once?
/* * * Search & Replace * * Use Ctrl+Shift+M to replace template values * */
set xact_abort on begin tran
declare @otxt varchar(1000) set @otxt = '<string1, text, text to be replaced>'
declare @ntxt varchar(1000) set @ntxt = '<string2, text, replacing text>'
declare @txtlen int set @txtlen = len(@otxt)
declare @ptr binary(16) declare @pos int declare @id int
declare curs cursor local fast_forward for select id, textptr(<field_name, sysname, target text field>), charindex(@otxt, <field_name, sysname, target text field>)-1 from <table_name, sysname, target table> where <field_name, sysname, target text field> like '%' + @otxt +'%'
open curs
fetch next from curs into @id, @ptr, @pos
while @@fetch_status = 0 begin print 'Text found in row id=' + cast(@id as varchar) + ' at pos=' + cast(@pos as varchar)
I have to periodically overwrite selected tables in one environment (Prod) with the contents of the same named tables from another environment (Staging).
There are about 200 tables involved.
In SQL Server what would be the best way to do this and minimize logging?
I will fetch records from table 1 based on tretmentid. get the count of records run the while loop inside loop I will compare the column values with the same table(table 1) for different tretmentid. if any one row matches will come out from loop and send status .
I've below value in a column with data type - TEXT
QU 221025U2V/AN G-DT DL A 5 1A- 11,5,SF,230,30162,LZ,2,118,0,0,10170,25,06
This text value has some special characters in it. and I could not paste the exact value as this text box is not allowing me to do so. So, for reference I've attached a screenshot (Capture.png) of the value.
I want to fetch last two values from this text i.e. 25 and 06. (It can be anything like 56R,06T but will be the last two values separated by comma)...
How do I use the CAST or CONVERT function in the code below, I require a third column (named Diff) which Minus the StartTime from the EndTime and the result is outputted in the third column (named Diff).
Calculation: @Diff = (@EndTime - @StartTime)
I still want the variables (@StartTime and @EndTime) to remain as nvarchar.
The code:
DECLARE @StartTime nvarchar(10) = '12:10'; DECLARE @EndTime nvarchar(10) = '12:30'; DECLARE @Diff time(1) = '00:00'; SELECT @StartTime AS '@StartTime', @EndTime AS '@EndTimes', @Diff AS '@Diff';
Hi all,What are the fundamentals (fundamental functions) that most small tomedium sized organizations that use MS SQL Server 7 or 2000 valuemost?What's your insight?OK, here's my biased definition of small to medium sized organization,annual revenue from 20m to 300m.Thanks.DL
I have a separate list of calendar years with radiocarbon year equivalents in SQL server but no conversion equation. Most but not all of the data I have is in radiocarbon years. I thought at first I could just link the tables but I don't want the data that is already in calendar years to be linked to this conversion table. Is there any way I can either link the two tables with criteria for which data is linked (Only ages that are in radiocarbon years). Or possibly a way to query all ages that are in radiocarbon years and do something similar to a find and replace with a large list of numbers to change?
