Oninit
Talk to an expert →

Informix Error -588: Invalid host variable number.

Cause and resolution

Invalid host variable number.

Database servers starting with Version 4.1 detect this internal error. If the error recurs, pleasnote all circumstances and contact IBM Informix Technical Support.

Oninit® Troubleshooting Guidance

Reasons / Common Causes

-588 is flagged by the official text as an internal error, detected by database servers starting with Version 4.1, with no documented application-level trigger — a mismatch somewhere between the number of host variables an embedded-SQL statement expects and what the client library actually passed.

  1. A client-library/driver internal inconsistency between the prepared statement's expected placeholder count and the host variables supplied at execute time — the general category of condition the error name implies.
  2. A version mismatch between the ESQL/C preprocessor-generated code and the runtime library it links against, similar in spirit to the client/server version-compatibility issue behind -516.
  3. A genuine internal engine/library condition, per the official guidance's framing, with no documented application-level cause.
Solutions / Resolution
  1. If this recurs, note all circumstances and contact IBM Informix Technical Support, per the official guidance — there is no documented general application-level fix.
  2. Check that the ESQL/C preprocessor and the runtime library are at matching, compatible versions, as a plausible concrete check worth ruling out before treating this as purely internal, given the error's connection to host-variable/placeholder bookkeeping.
  3. Capture the exact statement, host-variable list, and placeholder count involved for escalation if a version mismatch doesn't explain it.
Examples
Checking library/preprocessor versions
$ esql -V

Compare the ESQL/C preprocessor version against the runtime library actually linked into the program.

Diagnostic Checks
  1. Check ESQL/C preprocessor and runtime library version compatibility as a first concrete check.
  2. Capture the exact statement and host-variable list for escalation if no version mismatch is found.
Related Errors / Related Topics

No closely related error codes are cross-referenced for -588 in this set yet.

An internal host-variable bookkeeping error — check ESQL/C preprocessor/runtime version compatibility before escalating to IBM Informix Technical Support.