Bugs item #1796269, was opened at 2007-09-17 16:53
Message generated for change (Comment added) made by mlkersten
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=482468&aid=1796269&group_id=56967
Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: SQL/Core
Group: (zombie: MonetDB5 5.0)
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Sandor Heman (saanti)
Assigned to: Niels Nes (nielsnes)
Summary: SQL: hangs/crashes on 'exists' subqueries after a join
Initial Comment:
This query came up during ADT labwork session 1.
We use the VOC dataset, 32-bit/32-bit-oid mserver 5, Mars SR2, on UvA linux
machines:
uname -a
Linux ow126 2.6.12-1.1381_FC3smp #1 SMP Fri Oct 21 04:03:26 EDT 2005 i686 i686
i386 GNU/Linux
The original query hangs mserver without any resource consumption:
select count(*) from
craftsmen c,
passengers p
where c.trip = p.trip and exists
(select 1 from voyages v
where c.trip = v.trip and v.boatname = 'AMSTERDAM'
and v.departure_harbour ='Texel');
When reducing it to the below query, the server segfaults:
select count(*)
from craftsmen c,
passengers p
where c.trip = p.trip and exists (select 1) ;
without a join we get for both:
select count(*) from craftsmen c ;
select count(*) from craftsmen c where exists (select 1) ;
BOTH GIVE:
+--------+
| count_ |
+========+
| 2349 |
+--------+
1 row
----------------------------------------------------------------------
>Comment By: Martin Kersten (mlkersten)
Date: 2007-11-16 13:15
Message:
Logged In: YES
user_id=490798
Originator: NO
Niels, can it be closed?
----------------------------------------------------------------------
Comment By: Martin Kersten (mlkersten)
Date: 2007-09-18 23:39
Message:
Logged In: YES
user_id=490798
Originator: NO
This bug is not confirmed on the head MonetDB/SQL
There is no segfault
----------------------------------------------------------------------
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=482468&aid=1796269&group_id=56967
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2005.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Monetdb-bugs mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/monetdb-bugs
