SQL SERVER

Using Derived Tables

Gaurav Taneja — Tue, 11 Jan 2011 07:15:42 GMT

Using Derived Tables to Simplify the SQL Server Query Process

Problem
Sometimes querying data is not that simple and there may be the need to create temporary tables or views to predefine how the data should look prior to its final output. Unfortunately there are problems with both of these approaches if you are trying to query data on the fly.

With the temporary tables approach you need to have multiple steps in your process, first to create the temporary table, then to populate the temporary table, then to select data from the temporary table and lastly cleanup of the temporary table.

With the view approach you need to predefine how this data will look, create the view and then use the view in your query. Granted if this is something that you would be doing over and over again this might make sense to just create a view, but let's look at a totally different approach.

Solution
With SQL Server you have the ability to create derived tables on the fly and then use these derived tables within your query. In concept this is similar to creating a temporary table and then using the temporary table in your query, but the approach is much simpler, because it can all be done in one step.

Let's take a look at an example where we query the Northwind database to try to find out how many customers fall into various categories based on sales. The categories that we have predefined are as follows:

Total Sales between 0 and 5,000 = Micro
Total Sales between 5,001 and 10,000 = Small
Total Sales between 10,001 and 15,000 = Medium
Total Sales between 15,001 and 20,000 = Large
Total Sales > 20,000 = Very Large

There are several ways that this data can be pulled, but let's look at an approach using a derived table.

The first step is to find out the total sales by each customer, which can be done with the following statement.

SELECT   o.CustomerID,
         SUM(UnitPrice * Quantity) AS TotalSales
FROM     [Order Details] AS od
         INNER JOIN Orders AS o
           ON od.OrderID = o.OrderID
GROUP BY o.CustomerID

This is a partial list of the output:

CustomerID	TotalSales
CUST1	4596.2000
CUST2	1402.9500
CUST3	7515.3500
...
CUSTN	3531.9500

The next step is to classify the TotalSales value into the OrderGroups that were specified above:

SELECT   o.CustomerID,
         SUM(UnitPrice * Quantity) AS TotalSales,
         CASE
           WHEN SUM(UnitPrice * Quantity)
               BETWEEN 0 AND 5000 THEN 'Micro'
           WHEN SUM(UnitPrice * Quantity)
               BETWEEN 5001 AND 10000 THEN 'Small'
           WHEN SUM(UnitPrice * Quantity)
               BETWEEN 10001 AND 15000 THEN 'Medium'
           WHEN SUM(UnitPrice * Quantity)
               BETWEEN 15001 AND 20000 THEN 'Large'
           WHEN SUM(UnitPrice * Quantity)
               > 20000 THEN 'Very Large'
         END AS OrderGroup
FROM     [Order Details] AS od
         INNER JOIN Orders AS o
          ON od.OrderID = o.OrderID
GROUP BY o.CustomerID

This is a partial list of the output:

CustomerID	TotalSales	OrderGroup
CUST1	4596.2000	Micro
CUST2	1402.9500	Micro
CUST3	7515.3500	Small
...
CUSTN	3531.9500	Micro

The next step is to figure out how many customers fit into each of these groups and this is where the derived table comes into play. Take a look at the following query which uses a derived table called OG. What we are doing here is using the same query from the step above, but calling this derived table OG. Then we are selecting data from this derived table for our final output just like we would with any other query. All of the columns that are created in the derived table are now available for our final query.

SELECT   OG.OrderGroup,
         COUNT(OG.OrderGroup) AS OrderGroupCount
FROM     (SELECT   o.CustomerID,
                   SUM(UnitPrice * Quantity) AS TotalSales,
                   CASE
                     WHEN SUM(UnitPrice * Quantity)
                       BETWEEN 0 AND 5000 THEN 'Micro'
                     WHEN SUM(UnitPrice * Quantity)
                       BETWEEN 5001 AND 10000 THEN 'Small'
                     WHEN SUM(UnitPrice * Quantity)
                       BETWEEN 10001 AND 15000 THEN 'Medium'
                     WHEN SUM(UnitPrice * Quantity)
                       BETWEEN 15001 AND 20000 THEN 'Large'
                     WHEN SUM(UnitPrice * Quantity)
                       > 20000 THEN 'Very Large'
                   END AS OrderGroup
          FROM     [Order Details] AS od
                   INNER JOIN Orders AS o
                     ON od.OrderID = o.OrderID
          GROUP BY o.CustomerID) AS OG
GROUP BY OG.OrderGroup

This is the complete list of the output from the above query.

OrderGroup	OrderGroupCount
Large	10
Medium	11
Micro	33
Small	15
Very Large	20

Next Steps

Next time you run into a challenge of whether to create a temporary table or a view to produce the desired query take a look at using a derived table instead
Experiment with using derived tables, views and temporary tables to see what yields better performance results. There are several articles on the internet that have shown that using a derived table is faster then temporary tables, but try it for yourself.

Creating a new Job in Sql Step by Step

Gaurav Taneja — Tue, 11 Jan 2011 07:02:58 GMT

This is about adding a new SQL Jobs in the Sql Server 2005.

Step 1

Make sure that the SQL Server Agent is up and running. You can see it in the taskbar icon.

If SQL Server Agent is not running, start it from the SQL Server Configuration Manger

You can also start the SQL Server Agent from the command prompt using the command netstart

net start "SQL Server Agent (<instance name>)"

e.g net start "SQL Server Agent (SQLSERVER01)"

Step 2

Connect to the database engine of SQL server using SQL Server Management Studio.

Step 3

Expand the SQL Server Agent. You will see a Jobs folder over there. Right click on jobs and choose Add New.

Step 4

A New Job popup will appear. Specify the name of the job.

Step 5

Cilck next on the "Steps" in the left menu. A sql job can contain one or more steps. A step might be simply an sql statement or a stored procedure call. Add you step here

Job step added

Cilck next on the "Schedules" in the left menu. A sql job can contain one or more schedules. A schedule is basically the time at which sql job will run it self. You can specify recurring schedules also.

Job schedule added

You sql job is ready now. However there are other thing you can use if needed like Alert, Notifications etc.

Truncating All Tables

Gaurav Taneja — Mon, 29 Jun 2009 17:21:30 GMT

Create

Procedure GT_DeleteRecords_AllTables

/*********************************************************

Stored Procedure: GT_DeleteRecords_AllTables

Do not excute this proc

Purpose: Delete ALL records within ALL the tables in a DB with ease.

Test: Exec GT_DeleteRecords_AllTables**********************************************************/

Set

Exec

nocount on sp_MSForEachTable 'Alter Table ? NoCheck Constraint All'

Exec

sp_MSForEachTable

If ObjectProperty(Object_ID(''?''), ''TableHasForeignRef'')=1

Begin

-- Just to know what all table used delete syntax.

Print ''Delete from '' + ''?''

Delete From ?

End

Else

Begin

-- Just to know what all table used Truncate syntax.

Print ''Truncate Table '' + ''?''

Truncate Table ?

End

Exec

sp_MSForEachTable 'Alter Table ? Check Constraint All'

sp_xml_preparedocument

Gaurav Taneja — Tue, 14 Oct 2008 12:17:30 GMT

Example displaying when data is sent in form of xml document

CREATE PROCEDURE XMLINSERT

@intShowVersion   INT =0,
@strClassName   varchar(250),
@strLang varchar(10),
@strXml text='',
@intError int output


AS
SET NOCOUNT ON


/* @intShowVersion   INTEGER =0,
@strCreatedBy    VARCHAR(20) = '' ,
@intTemplateID   INTEGER = 0,
@dtClientCreatedOn   DATETIME = '' ,
@strUpdatedBy    VARCHAR(20) = '' ,
@dtClientUpdatedOn   DATETIME = '' ,
@strXml text='',




SET DATEFORMAT dmy

IF (@intShowVersion = 1 )
BEGIN
SELECT VERSION='$Revision: 1 $'
RETURN 0
END
ELSE
BEGIN
BEGIN TRAN --Transaction begins
-- DECLARE @intError INTEGER
    DECLARE @strDisplayref VARCHAR(200)
DECLARE @intTableId varchar(10)
Declare @StrQuery nvarchar(Max)
Declare @strDelQuery nvarchar(Max)
DECLARE @hDoc INT
Declare @strTableName nvarchar(100)
/*=============================================== START: INSERT INTO [*.Multilingual]==================================================*/


EXEC sp_xml_preparedocument @hDoc OUTPUT,@strXml

set @strDisplayref=(select Top 1 CPM.CM_DisplayReference_C from SF_ClassProperty_Master CPM
where CPM.CM_ClassIndexId_I =(Select CM.CM_ClassIndexId_I from Sf_Class_Master CM where CM.CM_ClassNAme_C=@strClassName) and CPM.CM_DisplayReference_C is not null )

set @strDisplayref= Substring(@strDisplayref,2,Len(@strDisplayref))
print @strDisplayref

set @intTableId = (Select CM_TableName_C from sf_class_master where CM_ClassNAme_C=@strClassName)
print @intTableId


set @strDisplayref = 'Rowid,[Language],'+ @strDisplayref
print @strXml

set @strTableName = ''+ @intTableId +'.Multilingual'
print @strTableName
IF EXISTS (SELECT 1 FROM sysobjects WHERE xtype='u' AND name=''+@strTableName+'')
Begin
set @strDelQuery =N'Delete from ['+ @intTableId +'.Multilingual] where [Language]='''+@strLang+''''
print @strDelQuery
exec sp_executesql @strDelQuery,N'@intTableId varchar,@strLang nvarchar(10)',@intTableId,@strLang


set @strQuery=N' INSERT INTO ['+ @intTableId +'.Multilingual] ('+ @strDisplayref+' )SELECT Rowid,Lang,DisplayRef FROM OPENXML(@hdoc, ''//*/RefValue'',1) WITH(Rowid Int,Lang nvarchar(10),DisplayRef nvarchar(500)) '

print @strquery
exec sp_executesql @strQuery,N'@hdoc int', @hdoc

/*=============================================== END: INSERT INTO [*.Multilingual]==================================================*/

EXEC sp_xml_removedocument @hDoc
End

/*=============================================== END: ==================================================*/
SELECT @intError = @@error
print @intError
IF @intError = 0
   BEGIN
    COMMIT TRAN
   END
ELSE
   BEGIN
    ROLLBACK TRAN
   END
END

SET NOCOUNT OFF

Count No of Procedure in Database

Gaurav Taneja — Tue, 06 May 2008 05:02:13 GMT

Count Procedure

select count(*) from sysobjects where xtype='P'

other option is below

select CASE(XType) WHEN 'C' THEN 'CHECK constraint'
WHEN 'D' THEN 'Default or DEFAULT constraint'
WHEN 'F' THEN 'FOREIGN KEY constraint'
WHEN 'L' THEN 'Log'
WHEN 'FN' THEN 'Scalar function'
WHEN 'IF' THEN 'Inlined table-function'
WHEN 'P' THEN 'Stored procedure'
WHEN 'PK' THEN 'PRIMARY KEY constraint (type is K)'
WHEN 'RF' THEN 'Replication filter stored procedure'
WHEN 'S' THEN 'System table'
WHEN 'TF' THEN 'Table function'
WHEN 'TR' THEN 'Trigger'
WHEN 'U' THEN 'User table'
WHEN 'UQ' THEN 'UNIQUE constraint (type is K)'
WHEN 'V' THEN 'View'
WHEN 'X' THEN 'Extended stored procedure' END Type
, Count(*) as total from sysObjects
GROUP BY xtype

Simple procedure using transaction

Gaurav Taneja — Mon, 07 Apr 2008 11:45:38 GMT

Begin
        Begin Tran
    --Inserting values member details into ServGeneralUser Table
            Insert into ServGeneralUser(LoginName,Password,Email,Address1,Address2,City,State,OtherStateName,Country,Zip,SecretQuestion,SecretAnswer,Photograph,usertype,updationdate,TnC)
            values
            (@LoginName,@Password,@Email,@Address1,@Address2,@City,@State,@OtherState,@Country,@Zip,@SecretQuestion,@SecretAnswer,@Phototgraph,'A',getdate(),'Y')

    -- reteriving Currently Inserted Members User Id into local variable @userId
            select @userId=ident_current('ServGeneralUser');
    --Inserting values member details into ServMemberDetails Table
            Insert into ServArtistDetails(Userid,ArtistName,Genre,SubGenre,OfficialWebsite,SignedForCompany,ProffesionalRepresentation,Motto,Influences)
            values
            (@userId,@ArtistName,@Genre,@SubGenre,@OffWebSite,@SignedForRecordCompany,@ProfessionalRepresentation,@Motto,@Influences)
                ----------------------------------------------------
                declare @Influence varchar(10)
                        Begin Tran
                        set rowcount 0
                        select * into #mytemp from split(@Influences,',')
                        set rowcount 1
                        select @Influence = data from #mytemp
                        while @@rowcount <> 0
                            begin
                               set rowcount 0
                               delete #mytemp where data = @Influence
                               set rowcount 1
                                if(select count(artist_id_7d) from artist_7d where artist_id_7d=@Influence)<=0
                                Begin
                                    set @ErrorCode='ERR2013'
                                    ROLLBACK TRAN
                                    select '0' as Result
                                    return
                                End
                               insert into ServArtistInfluences(UserId,ArtistInfluenceID)values(@userId,@Influence);
                               SELECT @intErrorCode = @@ERROR
                               IF (@intErrorCode <> 0)
                               Begin
                                    set @ErrorCode=@intErrorCode
                                    --print 'error occured while inserting record'
                                    ROLLBACK TRAN
                                    select '0' as Result
                                    return
                               End
                               select @Influence = data from #mytemp
                            end
                        set rowcount 0
                        drop table #mytemp
                        Commit Tran
                        set @ErrorCode='0';
                        select '1' as Result

                -----------------------------------------------------
            set @ErrorCode='0';

            SELECT @intErrorCode = @@ERROR
            IF (@intErrorCode <> 0) GOTO PROBLEM

        COMMIT TRAN

        PROBLEM:
        IF (@intErrorCode <> 0) BEGIN
            ROLLBACK TRAN
        END
    End

New in Visual Studio 2008

Gaurav Taneja — Wed, 02 Apr 2008 11:27:16 GMT

What is new in Visual Studio 2008

A quick list of some of the new features are:

Multi-Targeting support
Web Designer and CSS support
ASP.NET AJAX and JavaScript support
Project Designer
Data
LINQ – Language Integrated Query

The features listed and explained in this paper are not complete and this document intends to give you a forehand to start off with VS 2008.

1. Multi-Targeting Support

Earlier, each Visual Studio release only supported a specific version of the .NET Framework. For example, VS 2003 only works with .NET 1.1, and VS 2005 only works with .NET 2.0.

One of the major changes with the VS 2008 release is to support what Microsoft calls "Multi-Targeting". This means that Visual Studio will now support targeting multiple versions of the .NET Framework, and developers will be able to take advantage of the new features that Visual Studio provides without having to migrate their existing projects and deployed applications to use a new version of the .NET Framework.

Now when we open an existing project or create a new one with VS 2008, we can pick which version of the .NET Framework to work with. The IDE will update its compilers and feature-set to match the chosen .NET Framework.

Features, controls, projects, item-templates, and references that do not work with the selected version of the Framework will be made unavailable or will be hidden.

Unfortunately, support has not been included to work with Framework versions 1.1 and earlier. The present release supports 2.0/3.0 and 3.5 .NET Frameworks.

Microsoft plans to continue multi-targeting support in all future releases of Visual Studio.

Creating a New Project with Visual Studio 2008 that Targets .NET 2.0 Framework Library

The screenshots below depict the creation of a new web application targeting .NET 2.0 Framework. Choose File->New Project. As we see in the snapshot below in the top-right of the new project dialog, there is now a dropdown that allows us to choose which versions of the .NET Framework we want to target when we create the new project. The templates available are filtered depending on the version of the Framework chosen from the dropdown:

Can I Upgrade an Existing Project to .NET 3.5?

When we open a solution created using an older version of Visual Studio and Framework, VS 2008 would ask if migration is required. If we opt to migrate, then a migration wizard would start. If we wish to upgrade our project to target a newer version of the Framework at a later point of time, we can pull up the project properties page and choose the Target Framework. The required assemblies are automatically referenced. The snapshot below shows the properties page with the option Target Framework marked.

2. Web Designer, Editing and CSS Support

One feature that web developers will discover with VS 2008 is its drastically improved HTML designer, and the extensive CSS support made available.

The snapshots below depict some of the new web designer features in-built into VS 2008.

Split View Editing

In addition to the existing views, Design view and Code view, VS 2008 brings along the Split view which allows us to view both the HTML source and the Design View at the same-time, and easily make changes in any of the views. As shown in the image below, as we select a tag in code view, the corresponding elements/controls are selected in design view.

CSS Style Manager

VS 2008 introduces a new tool inside the IDE called "Manage Styles". This shows all of the CSS style sheets for the page.

It can be used when we are in any of the views - design, code and split views. Manage Styles tool can be activated by choosing Format -> CSS Styles -> Manage Styles from the menu. A snapshot of the same would look like the following:

Create a new style using the new style dialog window as show in the snapshot below.

Now, the style manager would show .labelcaption style as well in the CSS styles list. However, if we observe that the body element has a circle around it but the .labelcaption does not have one, this is because the style is not in use yet.

We will not select all the labels below and apply our new style .labelcaption.

We can choose to modify the existing style through GUI using "Modify style..." menu option in the dropdown menu as shown above or choose to hand edit the code by choosing the option "Go To Code".

CSS Source View Intellisense

The designer is equipped with the ability to select an element or control in design-view, and graphically select a rule from the CSS list to apply to it.

We will also find when in source mode that we now have intellisense support for specifying CSS class rules. The CSS Intellisense is supported in both regular ASP.NET pages as well as when working with pages based on master pages.

Code Editing Enhancements

Below is a non-exhaustive list of a few new code editing improvements. There are many more about which I don't know yet.

Transparent Intellisense Mode

While using VS 2005/2003 we often find ourselves escaping out of intellisense in order to better see the code around, and then go back and complete what we were doing.

VS 2008 provides a new feature which allows us to quickly make the intellisense drop-down list semi-transparent. Just hold down the "Ctrl" key while the intellisense drop-down is visible and we will be able to switch it into a transparent mode that enables us to look at the code beneath without having to escape out of Intellisense. The screenshot below depicts the same.

Organize C# Using Statements

One of the small, but a nice new feature in VS 2008 is support for better organizing using statements in C#. We can now select a list of using statements, right-click, and then select the "Organize Usings" sub-menu. When we use this command the IDE will analyze what types are used in the code file, and will automatically remove those namespaces that are declared but not required. A small and handy feature for code refactoring.

3. ASP.NET AJAX and JavaScript Support

JavaScript Intellisense

One new feature that developers will find with VS 2008 is its built-in support for JavaScript Intellisense. This makes using JavaScript and building AJAX applications significantly easier. A double click on HTML control in design mode would automatically create a click event to the button and would create the basic skeleton of the JavaScript function. As we see in the depicted image below, JavaScript Intellisense is inbuilt now. Other JavaScript Intellisense features include Intellisense for external JavaScript libraries and adding Intellisense hints to JavaScript functions.

JavaScript Debugging

One new JavaScript feature in VS 2008 is the much-improved support for JavaScript debugging. This makes debugging AJAX applications significantly easier. JavaScript debugging was made available in VS 2005 itself. However, we had to run the web application first to set the breakpoint or use the "debugger" JavaScript statement.

VS 2008 makes this much better by adding new support that allows us to set client-side JavaScript breakpoints directly within your server-side .aspx and .master source files.

We can now set both client-side JavaScript breakpoints and VB/C# server-side breakpoints at the same time on the same page and use a single debugger to step through both the server-side and client-side code in a single debug session. This feature is extremely useful for AJAX applications. The breakpoints are fully supported in external JavaScript libraries as well.

4. Few Other Features and Enhancements

Below is a list of few other enhancements and new features included in Microsoft Visual Studio 2008.

Project Designer

Windows Presentation Foundation (WPF) applications have been added to Visual Studio 2008. There are four WPF project types:

WinFX Windows Application
WinFX Web Browser Application
WinFX Custom Control Library
WinFX Service Library

When a WPF project is loaded in the IDE, the user interface of the Project Designer pages lets us specify properties specific to WPF applications.

Data

Microsoft Visual Studio 2008 Beta 2 includes the following new features to incorporate data into applications:

The Object Relational Designer (O/R Designer) assists developers in creating and editing the objects (LINQ to SQL entities) that map between an application and a remote database
Hierarchical update capabilities in Dataset Designer, providing generated code that includes the save logic required to maintain referential integrity between related tables
Local database caching incorporates an SQL Server Compact 3.5 database into an application and configures it to periodically synchronize the data with a remote database on a server. Local database caching enables applications to reduce the number of round trips between the application and a database server

LINQ – Language Integrated Query

LINQ is a new feature in VS 2008 that broadens great querying capabilities into the language syntax. LINQ introduces patterns for querying and updating data. A set of new assemblies are provided that enable the use of LINQ with collections, SQL databases, and XML documents.

Visual Studio 2008 Debugger

The Visual Studio 2008 debugger has been enhanced with the following features:

Remote debugging support on Windows Vista
Improved support for debugging multithreaded applications
Debugging support for LINQ programming
Debugging support for Windows Communications Foundation
Support for script debugging, including client-side script files generated from server-side script now appear in Solution Explorer

Reporting

Visual Studio 2008 provides several new reporting features and improvements such as:

New Report Projects: Visual Studio 2008 includes two new project templates for creating reporting applications. When we create a new Reports Application project, Visual Studio provides a report (.rdlc) and a form with a ReportViewer control bound to the report.
Report Wizard: Visual Studio 2008 introduces a Report Wizard, which guides us through the steps to create a basic report. After we complete the wizard, we can enhance the report by using Report Designer.
Expression Editor Enhancement: The Expression Editor now provides expressions that we can use directly or customize as required.
PDF Compression: The ReportViewer controls can now compress reports that are rendered or exported to the PDF format.

Function to convert DateTime to MM/DD/YYYY format + SQL SERVER

Gaurav Taneja — Wed, 02 Apr 2008 09:41:35 GMT

Function to convert DateTime to MM/DD/YYYY format

CreateFUNCTION [dbo].[tkfunConvertDateToMMDDYYYY](@dtDate varchar(10))
RETURNS VARCHAR(10)
AS
BEGIN
RETURN substring(@dtDate,4,2)+'/'+substring(@dtDate,1,2)+'/'+substring(@dtDate,7,4)
END

Function to Convert DateTime to DD/MM/YYYY format + SQL SERVER

Gaurav Taneja — Wed, 02 Apr 2008 09:40:15 GMT

Function to Convert DateTime to DD/MM/YYYY format

CreateFUNCTION [dbo].[tkfunConvertDateToDDMMYYYY](@dtDate varchar(10))
RETURNS datetime
AS
BEGIN
RETURN Convert(datetime,substring(@dtDate,4,2)+'/'+substring(@dtDate,1,2)+'/'+substring(@dtDate,7,4))
END

Remove Special Character from XML string + sql Server

Gaurav Taneja — Wed, 02 Apr 2008 09:38:18 GMT

Remove Special Character from string

-- =============================================
-- Author:        <Author,,Name>
-- Create date: <Create Date, ,>
-- Description:    <Description, ,>
-- =============================================
ALTER FUNCTION [dbo].[RemoveSpChar]
(
    -- Add the parameters for the function here
    @sInput varchar(MAX)=''
)
RETURNS varchar(MAX)
AS
BEGIN
    -- Declare the return variable here
    DECLARE @sOutput Varchar(MAX),
            @iIndex int,
            @iLength int,
            @sChar varchar(1),
            @iASCII int,
            @iLen int,
            @iRem int

    set @sInput= ltrim(rtrim(@sInput))
    set @iLength = len(@sInput)
    set @iIndex =1
    set @sOutput=''

    while @iIndex <= @iLength
    begin
        set @sChar=substring(@sInput,@iIndex,1)
        set @iASCII=ascii(@sChar)

        if ((@iASCII>=48 and @iASCII<=57) or (@iASCII>=65 and @iASCII<=90) or (@iASCII>=97 and @iASCII<=122) )
            set @sOutput=@sOutput+@sChar
            --return @sChar + ' - ' + convert(varchar,@iASCII)
        set @iIndex =@iIndex +1
    end

    if len(@sOutput)>17
        set @sOutput=substring(@sOutput,1,17)
    else if len(@sOutput)<6
    begin
        set @iLen=len(@sOutput)
        set @iRem=6-@iLen

        set @sOutput=substring(@sOutput + replicate('0',@iRem),1,6)

    end

    -- Return the result of the function
    RETURN @sOutput

END