Content Summary : Top Informix-PostgreSQL Conversion "Gotchas" (1) In Informix, the normal file extension for files with C code with embedded SQL is ".ec". In PostgreSQL, it is ".pgc". (2) Within an SQL statement, Informix denotes a string using double quotes (") or single quote ('). PostgreSQL denotes strings using single quotes (') only. Informix: SELECT * FROM Location WHERE lid = "BLUO2"; PostgreSQL: SELECT * FROM Location WHERE lid= 'BLUO2'; This is true for both ad hoc queries and .pgc files. Note that character strings in C are still denoted using double quotes. (3) The Informix utilities dbaccess and sqlcmd for ad hoc queries are replaced by a PostgreSQL utility called psql. (4) PostgreSQL does not implement an ISAM error code. (5) PostgreSQL error return codes are different from Informix. In Informix, inserting a duplicate record results in a -239 error. In PostgreSQL, this results in a -400 error. It is recommended that numeric error codes be replaced by the use of 5 char error state (sqlca.sqlstate). The value of these can be found in Appendix of the PostgreSQL Documentation.