Informix Error -33054: Updates are not allowed on a scroll cursor.

Cause and resolution

Updates are not allowed on a scroll cursor.

This UPDATE statement refers to a cursor that was declared with the SCROLL keyword. The UPDATE statement requires a cursor that has been declared FOR UPDATE to ensure that the proper level of locking is applied to the rows that will be updated. See the DECLARE statement in the IBM Informix Guide to SQL: Syntax for more information on the correct use of cursors.

Oninit® Troubleshooting Guidance

Reasons / Common Causes

-33054 fires when an UPDATE statement refers to a cursor declared with SCROLL — per the official guidance, UPDATE requires a cursor declared FOR UPDATE for proper locking.

An UPDATE targeting a cursor declared SCROLL (without FOR UPDATE), per the official guidance — the direct, only cause.

Solutions / Resolution

Declare the cursor FOR UPDATE, per the official guidance, consulting the DECLARE entry in the IBM Informix Guide to SQL: Syntax.

Examples

An UPDATE against a SCROLL-only cursor

DECLARE upd_cur SCROLL CURSOR FOR SELECT total FROM orders;
OPEN upd_cur;
FETCH upd_cur INTO :amt;
UPDATE orders SET total = :amt * 2 WHERE CURRENT OF upd_cur;
-- -33054: upd_cur has no FOR UPDATE

Corrected

DECLARE upd_cur SCROLL CURSOR FOR SELECT total FROM orders FOR UPDATE;

Diagnostic Checks

Check whether the targeted cursor's DECLARE includes FOR UPDATE, and add it if missing.

Related Errors / Related Topics

-33039 — "Updates are not allowed in singleton select." A related cursor/UPDATE restriction, on singleton SELECTs rather than SCROLL cursors.

An UPDATE targeted a SCROLL cursor without FOR UPDATE — add FOR UPDATE to the cursor's declaration.