Informix Error -4160: This expression cannot be used as the target of an assignment statement.

Reasons / Common Causes

-4160 fires when an illegal assignment target is used — per the official guidance, a common example is a name declared CONSTANT used as an assignment target; the official guidance also lists the statements that involve assignment: LET, SELECT...INTO, OPEN CURSOR...INTO, FETCH INTO, FOREACH...INTO, FOR (the iterator variable), INITIALIZE, and LOCATE. Only NewEra returns this error.

1. An assignment (via any of the listed statement forms) targeting an expression that isn't a valid assignment target, per the official guidance — the direct, only cause.

Solutions / Resolution

1. Assign to a genuine variable instead, checking whether the target was accidentally declared CONSTANT or is otherwise non-assignable.

Examples

Assigning to a constant via SELECT INTO

CONSTANT max_id = 9999
...
SELECT MAX(order_id) INTO max_id FROM orders
-- -4160: max_id is CONSTANT, not assignable

Corrected

DEFINE max_id INTEGER
SELECT MAX(order_id) INTO max_id FROM orders

Diagnostic Checks

1. Check the target of every assignment-style statement (LET, SELECT...INTO, OPEN CURSOR...INTO, FETCH INTO, FOREACH...INTO, FOR, INITIALIZE, LOCATE), and confirm it's a genuine, non-constant variable.

Related Errors / Related Topics

• -4071 — "Cannot assign to constant "name"." A closely related error, covering the same constant-assignment restriction specifically for LET-style assignment.

An assignment statement targets something that isn't a valid assignment target (often a constant) — assign to a genuine variable instead.