PowerCenter objects – Introduction

PowerCenter objects – Introduction

• A repository is the highest physical entity of a project in PowerCenter.

• A folder is a logical entity in a PowerCenter project. For example, Customer_Data is a folder.

• A workflow is synonymous to a set of programs in any other programming language.

• A mapping is a single program unit that holds the logical mapping between source and target with required transformations. A mapping will just say a source table by name EMP exists with some structure. A target flat file by name EMP_FF exists with some structure. The mapping doesn’t say in which schema this EMP table exists and in which physical location this EMP_FF table going to be stored.

• A session is the physical representation of the mapping. The session defines what a maping didn’t do. The session stores the information about where this EMP table comes from. Which schema, with what username and password can we access this table in that schema. It also tells about the target flat file. In which physical location the file is going to get created.

• A transformation is a sub-program that performs a specific task with the input it gets and returns some output. It can be assumed as a stored procedure in any database. Typical examples of transformations are Filter, Lookup, Aggregator, Sorter etc.

• A set of transformations, that are reusable can be built into something called mapplet. A mapplet is a set of transformations aligned in a specific order of execution.

As with any other tool or programing language, PowerCenter also allows parameters to be passed to have flexibility built into the flow. Parameters are always passed as data in flat files to PowerCenter and that file is called the parameter file.