Click the name of an operator to learn more: 

:= (assignment)	Assigns the result of an expression to a temporary variable.
& (statement separator)	Separates statements in an expression.
#ERRORS	Returns 1 if a record contains an error as indicated by the database error log, else 0.
#MV	Returns the missing value marker (-2147483647) for non-character fields.
#SUBSET	Returns 1 if a record has been flagged using the Database | Utilities | Subset Selection command, else 0.