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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
Other syntax segmentsThese topics describe syntax segments, which are language elements, such as database object names or optimizer directives, that appear as a subdiagram reference in the syntax diagrams of some SQL or SPL statements.
Routine modifier A routine modifier specifies characteristics of how a user-defined routine (UDR) behaves.
Modifier Descriptions
NEGATOR

NEGATOR

Use the NEGATOR modifier with UDRs that return Boolean values.

The NEGATOR modifier designates another user-defined function, called a negator function, as a companion to the current function. A negator function takes the same arguments as its companion function, in the same order, but returns the Boolean complement.

That is, if a function returns TRUE for a given set of arguments, its negator function returns FALSE when passed the same arguments, in the same order. For example, the following functions are negator functions:

equal(a,b)
notequal(a,b)

Both functions take the same arguments, in the same order, but return complementary Boolean values. When it is more efficient to do so, the query optimizer can use the negator function instead of the function that you specify.

To invoke a user-defined function that has a negator function, you must have the Execute privilege on both functions. In addition, the function must have the same owner as its negator function.