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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™.
DESCRIBE statementUse the DESCRIBE statement to obtain information about output parameters and other features of a prepared object before you execute it.
Describing a Statement with Runtime Parameters

Describing a Statement with Runtime Parameters

If the prepared statement contains parameters for which the number of parameters or parameter data types is to be supplied at runtime, you can describe these input values. If the prepared statement text includes one of the following statements, the DESCRIBE statement returns a description of each column or expression that is included in the list:

EXECUTE FUNCTION (or EXECUTE PROCEDURE)
INSERT
SELECT (without an INTO TEMP clause)
UPDATE
In HCL OneDB™, the IFX_UPDDESC environment variable, as described in the HCL OneDB Guide to SQL: Reference, must be set before you can use DESCRIBE to obtain information about an UPDATE statement.

The description includes the following information:

The data type of the column, as defined in the table
The length of the column, in bytes
The name of the column or expression

For a prepared INSERT or UPDATE statement, DESCRIBE returns only the dynamic parameters (those expressed with a question mark (?) symbol). Using the OUTPUT keyword, however, prevents these from being returned.

You can specify a destination for the returned information as a new or existing system-descriptor area, or as a pointer to an sqlda structure.

A system-descriptor area conforms to the X/Open standards.