This reference manual for the INGRES data base system documents the use of INGRES in a very terse manner. It is divided into four parts: (1) Quel: describes the commands and features which are used inside of INGRES; (2) Unix: describes the INGRES programs which are executable as UNIX commands; (3) Files: describes some of the important files used by INGRES; and (4) Error: lists all the user generatable error messages along with some elaboration as to what they mean or what we think they mean.
