Informix Error -711: Cannot insert encoded BLOB descriptor.

Reasons / Common Causes

-711 fires when inserting an encoded BLOB descriptor via DESCR() fails — per the official guidance, the accompanying ISAM error carries the specific reason.

1. An underlying ISAM-level error during the insert, per the official guidance's pointer to checking the accompanying ISAM error — the only documented path to the specific cause.
2. Optical Subsystem-level storage issues (media, jukebox/library status), a plausible category given the surrounding family of optical-cluster/BLOB-descriptor errors, though not explicitly named by the sparse official text.

Solutions / Resolution

1. Check the accompanying ISAM error code, per the official guidance — the only documented path to the specific underlying cause.
2. Confirm the target column is on optical media, ruling out the -712 condition, since inserting into a non-optical BLOB column would be reported as -712 specifically, not -711.
3. Check Optical Subsystem storage availability as a plausible contributor.

Examples

Checking the accompanying ISAM error

-- Review the ISAM error code reported alongside -711 for the specific
-- underlying reason DESCR()'s insert failed.

Diagnostic Checks

1. Check the accompanying ISAM error code first, per the official guidance.
2. Confirm the target column is TEXT/BYTE stored on optical media.

Related Errors / Related Topics

• -712 — "Cannot insert encoded BLOB descriptor in non-optical BLOB columns." A more specific form of this failure, for the particular case of targeting a non-optical BLOB column.
• -713 — "Cannot decode encoded BLOB descriptor." A related DESCR() failure, at the decode stage rather than insert.
• -714 — "Cannot encode BLOB descriptor." A related DESCR() failure, at the encode stage.

A general DESCR() insert-failure indicator — the accompanying ISAM error carries the specific reason.