You can use the Expression Editor to create expressions. Based on the type of expression that you create, you can select fields, PowerCenter functions, and Data Validation Option parameters in the Expression Editor.
To prevent expressions that are not valid because of misspellings and syntax, you can select fields, PowerCenter functions, and Data Validation Option parameters in the Expression Editor. You can select PowerCenter functions from the
Functions
tab when you create a PowerCenter expression. If you create an expression that is processed by the data source, the
Functions
tab does not appear when you create the expression.
You can select a parameter from the
Parameters
tab when you create a WHERE clause for a single table or table pair. The
Parameters
tab shows all parameters that are defined in the parameter file that is associated with the single table or table pair. If you do not configure a parameter file for the single table or table pair, the
Parameters
tab does not appear when configure the WHERE clause.
The following figure shows a sample WHERE clause expression in the Expression Editor:
You can click
Validate
to validate a PowerCenter expression. The Expression Editor does not validate datatypes, precisions, scales, or expressions that the data source processes.