Book Image

Microsoft SQL Server 2012 Integration Services: An Expert Cookbook

Book Image

Microsoft SQL Server 2012 Integration Services: An Expert Cookbook

Overview of this book

SQL Server Integration Services (SSIS) is a leading tool in the data warehouse industry - used for performing extraction, transformation, and load operations. This book is aligned with the most common methodology associated with SSIS known as Extract Transform and Load (ETL); ETL is responsible for the extraction of data from several sources, their cleansing, customization, and loading into a central repository normally called Data Warehouse or Data Mart.Microsoft SQL Server 2012 Integration Services: An Expert Cookbook covers all the aspects of SSIS 2012 with lots of real-world scenarios to help readers understand usages of SSIS in every environment. Written by two SQL Server MVPs who have in-depth knowledge of SSIS having worked with it for many years.This book starts by creating simple data transfer packages with wizards and illustrates how to create more complex data transfer packages, troubleshoot packages, make robust SSIS packages, and how to boost the performance of data consolidation with SSIS. It then covers data flow transformations and advanced transformations for data cleansing, fuzzy and term extraction in detail. The book then dives deep into making a dynamic package with the help of expressions and variables, and performance tuning and consideration.
Table of Contents (23 chapters)
Microsoft SQL Server 2012 Integration Services: An Expert Cookbook
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Precedence Constraints: how to control the flow of task execution


Precedence Constraints are arrows in the Control Flow which define execution priority of tasks and other executables in the Control Flow. In the samples of this book till now we used simple Precedence Constraints a lot.

In this recipe, we will explore a new way of using Precedence Constraints and we will implement an if condition in the Control Flow with Precedence Constraints.

Also, we will reveal options to work when there are multiple Precedence Constraints for each executable.

How to do it...

  1. Create a SSIS project and name it as R06_Precedence Constraints.

  2. Create a RecordCount package variable of type int32. Set the default value to 0.

  3. Add an Execute SQL Task into the Control Flow, create an OLE DB Connection to the AdventureWorks2008R2 database.

  4. Type the following query in the SQL Statement property:

    SELECT COUNT(*) AS Cnt
    FROM Sales.Customer
    WHERE DATEDIFF(Day, ModifiedDate, GETDATE()) < 0
  5. As the previous statement will return...