To configure expression masking, you create an expression in the

Expression Builder

.

Select column, functions, variables, and operators to build expressions. The expression can reference input columns and output columns.

In expression masking, you can append additional data to the source column data. For example, you want to mask the first names. The source has the FirstName column and you want to concatenate the values in the FirstName column with the string ABC. When you configure the data masking rule, select the FirstName column and enter the following expression in the expression editor.

When you configure expression masking for a column, the column name appears as the expression by default.

Select functions, columns, variables, and operators from the point-and-click interface to minimize errors when you build expressions.

When you create an expression, verify that the expression returns a value that matches the column data type. The

Integration Service

returns zero if the return value does not match a numeric column. It returns NULL if the return value does not match a string column.

You cannot perform expression masking with repeatable output for Hadoop data sources.

For information about expression syntax, see the

Informatica Transformation Language Reference

.