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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
SELFUNC (C)Use the SELFUNC modifier with a C UDR to name a companion user-defined function, called a selectivity function, to the current UDR. The selectivity function provides selectivity information about the current UDR to the optimizer.

SELFUNC (C)

Use the SELFUNC modifier with a C UDR to name a companion user-defined function, called a selectivity function, to the current UDR. The selectivity function provides selectivity information about the current UDR to the optimizer.

The selectivity of a UDR is an estimate of the fraction of the rows that the query will select. That is, it is an estimate of the number of times the UDR will execute.

To execute sel_func, you must have Execute privilege on it and on the UDR.