Check for ANSI-standard SQL syntax

When you compile the Informix® ESQL/C program, you can instruct the preprocessor to check for Informix® extensions to ANSI-standard SQL syntax in one of two ways:

• You can set the DBANSIWARN environment variable.

  After you set the DBANSIWARN environment variable, every time you compile or run the Informix® ESQL/C program, Informix® ESQL/C checks for ANSI compatibility. For information about how to set DBANSIWARN, see the Informix® Guide to SQL: Reference. For details about how to check for runtime warnings, see Opaque data types. For details on how to set environment variables, see the Informix® Client Products Installation Guide for your operating system.

• You can specify the -ansi option at compile time whenever you want to check for ANSI compatibility.

  The -ansi option does not cause Informix® ESQL/C to check for ANSI compatibility at run time.

With the -ansi option, the Informix® ESQL/C preprocessor generates a warning message when it encounters the Informix® extension to ANSI SQL syntax. The following esql command preprocesses, compiles, and links the demo1.ec program and verifies that it does not contain any Informix® extensions to the ANSI-standard syntax:

esql -ansi demo1.ec