Expression Search 

Notice that the second row of the free-form search grid does not correspond to a field in the table either. Instead it is labeled Expression and supports a special kind of free-form search. With Expression search, you can enter an arbitrary expression that performs a complex set of tests, including various arithmetic, string, and logical operators, and performed on multiple fields and attributes at the same time rather than just a single field. When you perform an Expression search, the MDM Client evaluates the expression on each record and returns the set of records for which the expression is either TRUE or FALSE, depending upon the selected operator.

An expression that returns a NULL result evaluates to: (1) TRUE for validations (validation SUCCESS); and (2) FALSE for search (included in the search results for the is FALSEoperator).

When you double-click on the Value cell, MDM opens the Validation Expression dialog shown in the following figure.

For more information about how to use the Validation Expression dialog, see Validating Records.