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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 INPUT statementUse the DESCRIBE INPUT statement to return input parameter information before a prepared statement is executed.
Describing a Statement with Dynamic Runtime Parameters

Describing a Statement with Dynamic Runtime Parameters

If the prepared statement specifies a set of parameters whose cardinality or data types must be supplied at runtime, you can describe these input values. If the prepared statement text includes one of the following statements, the DESCRIBE INPUT statement returns a description of each column or expression that is included in the list:

EXECUTE FUNCTION (or EXECUTE PROCEDURE)
INSERT or SELECT
UPDATE or DELETE

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
Information about dynamic parameters (parameters that are expressed as question ( ? ) mark symbols within the prepared statement)

If the database server cannot infer the data type of an expression parameter, the DESCRIBE INPUT statement returns SQLUNKNOWN as the data type.

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.