Informix Error -863

Reasons / Common Causes

-863 fires when ALTER FRAGMENT ... DETACH is attempted on a table that still has ROWID — per the official guidance, ROWID must be dropped first.

1. ALTER FRAGMENT ... DETACH attempted while the table still has a ROWID column, per the official guidance — the direct, only cause.

Solutions / Resolution

1. Drop ROWID first, per the official guidance, then perform the detach — DETACH requires the PARTITION keyword unless the fragment identifier is itself the name of the dbspace where the fragment is stored:

   ALTER TABLE orders DROP ROWIDS;
   ALTER FRAGMENT ON TABLE orders DETACH PARTITION east_partition orders_east;
   

2. Consult the ALTER FRAGMENT ... DETACH syntax in the IBM Informix Guide to SQL: Syntax, per the official guidance's own pointer, for the full documented requirements.

Examples

The disallowed attempt

ALTER FRAGMENT ON TABLE orders DETACH PARTITION east_partition orders_east;
-- -863: orders still has a ROWID column

Corrected — drop ROWID first

ALTER TABLE orders DROP ROWIDS;
ALTER FRAGMENT ON TABLE orders DETACH PARTITION east_partition orders_east;

Diagnostic Checks

1. Check whether the table has a ROWID column before attempting a detach.

Related Errors / Related Topics

• -855 — "Cannot drop rowids on a non-fragmented table." A related ROWID-management restriction — this detach-prerequisite drop only makes sense on a fragmented table anyway, since -855 blocks it on non-fragmented ones.
• -864 — "Cannot attach a table with rowids." The mirror-image restriction: ROWID must also be dropped before an ATTACH, not just a DETACH.

Drop ROWID first (ALTER TABLE ... DROP ROWIDS), then perform the detach.