A function is variant if it can return different results when it is invoked with the same arguments or if it modifies the state of a database or of a variable. For example, a function that returns the current date or time is a variant function.
By default, user-defined functions are variant. If you specify NOT VARIANT when you create or modify a function, it cannot contain any SQL statements.
If the function is nonvariant, the database server might cache the return variant functions. For more information on functional indexes, see CREATE INDEX.
To register a nonvariant function, add the NOT VARIANT option in this clause or in the Routine Modifier clause that is discussed in Routine Modifier. If you specify the modifier in both contexts, however, you must use the same modifier (either VARIANT or NOT VARIANT) in both clauses.
Enterprise Edition Home | Express Edition Home | [ Top of Page | Previous Page | Next Page | Contents | Index ]