HiI have a performance issue on a query where I need all parent record and from
child table I only want a flag if there is any child record matching a
condition,so I write something like that:
SELECT P.ID,IIF(SUB.ID IS NULL,0,1) AS ISDATA FROM PARENT P LEFT JOIN
(SELECT FIRST 1 PA.ID FROM
Hi,
i suppose this one is much faster
SELECT P.ID
, CASE WHEN EXISTS(SELECT * FROM CHILD C WHERE C.ID_PARENT=P.ID AND
C.MYFIELD=3)
)
THEN 1 ELSE 0 END AS ISDATA
FROM PARENT P
INNER JOIN TABLE3 T3 ON P.ID=T3.
INNER JOIN TABLE3 T4 ON P.ID=T4.
...
Regards,
K
indeed much better
thanks!
On Friday, July 19, 2019, 02:34:20 PM GMT+3, liviuslivius
liviusliv...@poczta.onet.pl [firebird-support]
wrote:
Hi, i suppose this one is much faster SELECT P.ID, CASE WHEN EXISTS(SELECT *
FROM CHILD C WHERE C.ID_PARENT=P.ID AND C.MYFIELD=3) ) THEN
