Header files included in your program

The preprocessor automatically includes the following header files in your program:
  • The sqlhdr.h file provides cursor-related structures for your program.

    This header file automatically includes the sqlda.h and ifxtypes.h header files.

  • The sqlca.h file, which allows your program to check the success or failure of your statements with the SQLSTATE or SQLCODE variable
Restriction: Although you can now use an ANSI C compiler, the preprocessor does not fully support ANSI C, so you might not be able to preprocess all programs that follow the ANSI C standards.
To include any of the other header files in your program, you must use the include preprocessor directive. However, you only need to include the header file if your program refers to the structures or the definitions that the header file defines. For example, if your program accesses datetime data, you must include the datetime.h header file, as follows:
EXEC SQL include datetime.h;
Make sure to terminate the line of code with a semicolon. Some additional examples follow:
EXEC SQL include varchar.h;
EXEC SQL include sqlda;
$include sqlstype;
Tip: You do not have to enter the .h file extension for the header file; the esql preprocessor assumes a .h extension.