User3866881 posted
Not quite be sure about what you mean：）
You'd better paste all of your sql query codes.
As far as I know, this kind of problem usually happens when your update sql query doesn't look like an Update itself. Something like this:
UPDATE CLOG SET CLOG.NEXTDUE = (
SELECT H1.paidthru
FROM CTRHIST as H1
WHERE H1.ACCT = clog.ACCT AND
H1.SEQNO = (
SELECT MAX(SEQNO)
FROM CTRHIST
WHERE CTRHIST.ACCT = Clog.ACCT AND
CTRHIST.AMTPAID > 0 AND
CTRHIST.DATEPAID < CLOG.UPDATED_ON
)
)
WHERE CLOG.NEXTDUE IS NULL;
If you use this kind of codes, it will raise the error.
Because the bold statement will return a collection of data by the compiler's thinking. So it cannot be regarded as a correct statement of update statement when running.
About "How to solve the problem", please see what hans-v's suggestion：）
