Containers

Containers are a new concept in SSIS that didn't previously exist in SQL Server. They are a core unit in the SSIS architecture that help you logically group tasks together into units of work or create complex conditions. By using containers, SSIS variables and event handlers (these will be discussed in a moment) can be defined to have the scope of the container instead of the package. There are four types of containers that can be employed in SSIS:

• Task host container: The core type of container that every task implicitly belongs to by default. The SSIS architecture extends variables and event handlers to the task through the task host container.

• Sequence container: Allows you to group tasks into logical subject areas. In BIDS, you can then collapse or expand this container for usability.

• For loop container: Loops through a series of tasks for a given amount of time or until a condition is met.

• For each loop container: Loops through a series of files or records in a data set and then executes the tasks in the container for each record in the collection.

As you read through this book, you'll gain lots of experience with the various types of containers.