Long identifiers

HCL Informix® allows identifiers of up to 128 characters in length, and user names up to 32 characters in length. Other versions of Informix database servers support an identifier length of 18 characters and a user name length of 8 characters.

The database server uses the following two criteria to determine whether the client program can receive long identifiers:

The internal version number of the client program
The setting of the IFX_LONGID environment variable

If the IFX_LONGID environment variable is set to 0 (zero) the database server treats the client as if it cannot handle long identifiers. If IFX_LONGID is set to 1 (one) and the client version is recent enough, then the database server treats the client as if it is able to receive long identifiers. If IFX_LONGID is not set it is treated as if it is set to 1 (one).

Important: If you set IFX_LONGID in the environment of the client, it takes effect only for that client. If you set the IFX_LONGID environment variable in the environment of the database server, it takes effect for all client programs.

For more information about the IFX_LONGID environment variable, see the HCL Informix Guide to SQL: Reference.

Client programs that meet the following conditions can use long identifiers and long user names without recompiling:

It was compiled with a version of ESQL/C that was released later than version 9.20
It uses shared libraries (that is, program was compiled without the -static option)

If the database server truncates a long identifier or long user name, it sets the SQLSTATE variable to ‘01004’ and sets the sqlwarn1 flag to ‘W’ in the SQL Communications Area (sqlca).