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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.
External Routine Reference Include the External Routine Reference clause when you write an external routine. This option is not available for SPL routines.
Example of a C User-Defined Function

Example of a C User-Defined Function

The next example registers an external function named equal( ) that takes two point data type values as arguments. In this example, point is an opaque data type that specifies the x and y coordinates of a two-dimensional point.

CREATE FUNCTION equal( a point, b point ) RETURNING BOOLEAN;
   EXTERNAL NAME "/usr/lib/point/lib/libbtype1.so(point1_equal)"
   LANGUAGE C
END FUNCTION;

The function returns a single value of type BOOLEAN. The external name specifies the path to the C shared-object file where the object code of the function is stored. The external name indicates that the library contains another function, point1_equal( ), which is invoked while equal( ) executes.

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