Informix Error -690

Reasons / Common Causes

-690 fires when the server can't validate a referential constraint because it can't read the keys from the referencing (child) table — per the official guidance, the accompanying ISAM error carries the specific reason, and there's one specific, named requirement: if cascading deletes are in use, database logging must be on.

1. Cascading deletes used on an unlogged database, per the official guidance — the specific, named requirement; cascading deletes require logging to be enabled.
2. An underlying ISAM-level error while reading the referencing table's keys, per the official guidance's pointer to checking the accompanying ISAM error, for causes other than the logging requirement.

Solutions / Resolution

1. If using cascading deletes, confirm the database has logging enabled, per the official guidance — this is a hard requirement, not optional:

   SELECT name, is_logging FROM sysmaster:sysdatabases WHERE name = 'target_db';
   

2. Check the accompanying ISAM error code, per the official guidance, for causes other than the logging requirement.
3. If logging is off and can't be turned on for this database, don't rely on cascading deletes — delete from the referencing table explicitly before deleting from the referenced table instead.

Examples

Checking whether logging is on

SELECT name, is_logging FROM sysmaster:sysdatabases WHERE name = 'stores7';

An explicit delete sequence, when cascading isn't available

DELETE FROM order_items WHERE order_id = 42;
DELETE FROM orders WHERE order_id = 42;

Diagnostic Checks

1. Check is_logging in sysmaster:sysdatabases first, per the official guidance's specific named requirement for cascading deletes.
2. Check the accompanying ISAM error code for other causes if logging is confirmed on.

Related Errors / Related Topics

No closely related error codes are cross-referenced for -690 in this set yet.

Check whether the database has logging enabled first — cascading deletes require it, per the official guidance's specific named requirement.