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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.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
CREATE OPCLASS statementUse the CREATE OPCLASS statement to create an operator class for a secondary-access method.
SUPPORT Clause

SUPPORT Clause

Support functions are functions that the secondary-access method uses internally to build and search the index. Specify these functions for the secondary-access method in the SUPPORT clause of the CREATE OPCLASS statement.

You must list the names of the support functions in the order that the secondary-access method expects. For the specific order of support operators for the default operator classes for a B-tree index and an R-tree index, refer to Default Operator Classes.

The support function is an external function. CREATE OPCLASS does not verify that a specified support function exists. For the secondary-access method to use a support function, however, the support function must meet these criteria:

Be compiled in a shared library
Be registered in the database with the CREATE FUNCTION statement