Service Oriented Architecture Podcast

A compilation of podcasts related to Service Oriented Architecture (SOA) spread across the internet.

What is SOA? From whatis.com, sponsored by IBM

Another good article explaining what is SOA?
An introduction to SOA on Javaworld.com

Microsoft Excel 2010

Get a sneak preview of Microsoft's most famous BI Tool Excel in a new avatar Excel 2010 here.

http://www.microsoft.com/office/2010/

Count Distinct Records for Multiple Column

We all know how to find the Distinct Count for any particular column in a table

SELECT COUNT(DISTINCT ColumnName) FROM dbo.TableName

What if you want to count the Distinct combination for multiple Columns? The above syntax will not work. You can use a Derived table to count the distinct combination

SELECT COUNT(*) FROM (
SELECT DISTINCT Column1, Column2, Column3 FROM dbo.TableName) AS DistinctTable

Hope this helps!!

Create a Duplicate table

There are often times when I want to create a duplicate structure of an existing table. The simplest way to do that is following:

SELECT TOP 0 * INTO dbo.tablename

Remember to put a dbo before the new tablename, or else SQL Server creates the table under your schema.

Phases of Development Projects

I was watching the following Microsoft Webcast
IT Manager Webcast: How Microsoft IT Manages Vendor Development Projects (Level 300)

Lots of interesting sheets, graphs and tracker. Also, liked the following phases listed in Development Project. This can act as a Ready Reckoner.

• REQ - Requirements
• HLD - High Level Design (e.g. FSPEC)
• HLDINSP - High Level Design Inspection
• DLD - Detail Design
• DLDR - Detail Design Review
• DLDINSP - Detail Design Inspection
• TCR - Test Case Review
• CODE - Coding
• CR - Code Review
• UT - Unit Test
• CODEINSP - Code Inspection
• IT - Integration Testing
• ST - System Testing
• PM - Post-mortem
• STRAT - Strategy (e.g. Vision/Scope)
• PLAN - Planning, Project Management
• UAT - User Acceptance Test
• PL - Product Live

Impact of Multi-Column Clustered Index

Clustered Indexes are really important and special. Special because there can only be 1 Clustered Index in a table and they decide the order in which data is stored in tables.

Clustered Index help the database uniquely identify individual rows in a table. As mentioned in my previous blog if the Clustered Index do not uniquely identify a row, SQL Server automatically adds a 4 byte uniqueidentifier column to make it unique.

However we should be really careful not to add too many columns in a Clustered Index in trying to make it unique, because all Non-Clustered Indexes store the columns from Clustered Index at the end to point to a row in a table.

Therefore, more the no. of columns in a Clustered Index will be, more the size of Non-Clustered Index will be.