As explained in the Advanced DataWindows session, you can set a column as a "value required" column. That means, when the column gets focus, user can’t tab out of the column unless he enters a value in the column. However, if the user don’t go into that column at all, then, PowerBuilder is not going to force the user for the value. One good thing is that, you can call FindRequired() function to check columns that needs a value but has no value, before you save the changes in the database. If you would like to use the PFC service instead of calling FindRequired(), first you need to turn on the service:

dw_product.of_CheckRequired( Primary!, ll_Row, ll_Col, &ls_ColumnName, TRUE )

Parameter No	Description
First	The buffer to check. Valid values are Primary!, Filter!
Second	The row number from which the search should start. PowerBuilder stores the first error row number in this parameter.
Third	The first column number from which the search should start. PowerBuilder stores the first error column number in this parameter.
Fourth	After search, PowerBuilder stores the error column name
Fifth	True/False. True means, search only those columns that have been changed or added. Otherwise, PowerBuilder checks all rows and columns.

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