Command elements
Here are the rules for field names and expressions
specified on the Open Query File (OPNQRYF) command parameters, as well as
a wide range of built-in functions that the OPNQRYF command supports.
Field names
Field names specified on the Open Query File (OPNQRYF) command parameters must follow these rules.
Expressions
The expressions specified on the Open Query File (OPNQRYF) command parameters must follow these conventions.
Built-in functions
These built-in functions are supported for an expression that is used to define a derived field on the MAPFLD parameter or for a complex selection operand specified on the QRYSLT or GRPSLT parameter.
Restricted built-in functions
Some built-in functions are restricted in the way certain relational operators are specified on the QRYSLT and GRPSLT parameters.