Specifying the expression
Since a user might have just entered a value in the column,
validation rules refer to the current data value, which you can
obtain through the GetText DataWindow expression function.
Using GetText ensures that the most recent data entered in the
current column is evaluated.
PowerBuilder does the conversion for you
If you have associated a validation rule for a column in the
Database painter, PowerBuilder automatically converts the syntax
to use GetText when you place the column in a DataWindow
object.
GetText returns a string. Be sure to use a data conversion
function (such as Integer or Real) if you want to compare the
entered value with a datatype other than string.
For more on the GetText function and text patterns, see the section called “GetText” in DataWindow Reference and the section called “Match” in DataWindow Reference.
Referring to other
columns
You can refer to the values in other columns by specifying
their names in the validation rule. You can paste the column names
in the rule using the Columns box.