At 17:10 26.02.2003 +0900, you wrote:

>Using with IBPhenix ODBC driver or using with IBX dos'nt raise this error.
>
>Is this dbXpress driver Bug?

I don't know, but change your code to

UPDATE
T_KOUJI_P_GYOUSYA
SET
GYOUSYA_LIST_NO = 1560 ,
UPDATEUSER = 'tomneko' ,
LASTUPDATE = '2003-02-25'
WHERE
GYOUSYA_LIST_NO = 1591 AND
EXISTS(SELECT 1
FROM
T_KOUJI_PRIVATE KP
WHERE
KP.KOUJI_P_NO = T_KOUJI_P_GYOUSYA.KOUJI_P_NO AND
KP.BUKKEN_NO = 55 AND
KP.TENKEN_CODE = 3
);

IN (<subselect>) is a legal construct, but executes terribly slow (well, at
least if there are many records with GYOUSYA_LIST_NO = 1591 or many records
woth BUKKEN_NO = 55 AND TENKEN_CODE = 3). If this is a dbXpress bug, I
almost hope they don't fix it.

HTH,
Set