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Client APIs and toolsYou can use the HCL OneDB™ implementation of client APIs to develop applications for HCL OneDB™ database servers.
ESQL/C GuideThe HCL OneDB™ ESQL/C Programmer's Manual explains how to use , the HCL OneDB™ implementation of Embedded Structured Query Language (SQL) for C (ESQL/C), to create client applications with database-management capabilities.
Dynamic SQL
Determine SQL statementsIf you do not know until run time what SQL statement to execute, you can dynamically determine that statement with the DESCRIBE statement and use a dynamic-management structure to hold any values that the statement sends to or receives from the database server.
Dynamic-management structureIf you do not know the number or data types of values sent to or received from the database server, use a dynamic-management structure. A dynamic-management structure allows you to pass a variable-length list of data to the database server, or receive a variable-length list of data from it.
A system-descriptor areaA system-descriptor area is an area of memory declared by to hold data either returned from or sent by a prepared statement. It is the dynamic-management structure that conforms to the X/Open standards.
Fixed-length portion

Fixed-length portion

The fixed-size portion of the system-descriptor area consists of the single field, which following table shows.

Table 1. Field in the fixed-size portion of a system-descriptor area
Field	Data type	Description
COUNT	short	The number of column values or occurrences in the system-descriptor area. This is the number of item descriptors, one for each column. The DESCRIBE...USING SQL DESCRIPTOR statement sets COUNT to the number of described columns. You must use SET DESCRIPTOR to initialize the field before you send column values to the database server.