The SQLDA (SQL Descriptor Area) is an interface structure that is used for dynamic SQL statements. The structure passes information regarding host variables and SELECT statement results to and from the database. The SQLDA is defined in the header file sqlda.h.
There are functions in the database interface library or DLL that you can use to manage SQLDAs. For descriptions, see Library function reference.
When host variables are used with static SQL statements, the preprocessor constructs a SQLDA for those host variables. It is this SQLDA that is actually passed to and from the database server.
The SQLDA header file
SQLDA host variable descriptions
SQLDA sqllen field values