Dynamic ESQL and the SQL Descriptor Area
Many Dynamic ESQL statements require a data structure (SQL descriptor area) to describe and exchange data between your application and the ESQL-LIB interface. This data structure takes the place of C variables declared for the same purpose in Static ESQL statements.
The C structure definition for this SQL descriptor area is contained in the
proesql.h
header file in your ESQL installation directory. It consists of a single SQLDA_T structure that includes an array of pointers to SQLVAR_T structures, one for each table column or parameter marker. You must declare a pointer to each SQL descriptor area to use. An SQL descriptor area is not bound to a particular SQL request, but is the mechanism by which data is exchanged. You can use a single SQL descriptor area to fetch values from one table and insert those values in another. For more information on the SQL descriptor area, see Programming with ESQL."
Copyright © 2004 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095 |