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

For Loop Container: looping through static enumerator till a condition is met


The For Loop Container is a method to create looping in the SSIS package Control Flow and is very similar to the For Loop structure that exists in programming languages. In this looping container, SSIS optionally initializes an expression and repeats its workflow until the expression evaluates to false.

As mentioned previously, this container repeats something until a condition in the EvalExpression property evaluates to true. Some examples could be as follows:

  • Doing something n times

  • Wait for some time (seconds, minutes, hours...) in each interaction until a specific action takes place; for example until a flag stored in a database changes

  • Wait until a specific date and time to do something

To configure this container three important properties must be considered:

  • InitExpression : An optional initialization expression for the loop counter.

  • EvalExpression: This evaluates an expression and must be true, otherwise the...