SQL query brings database server down
We are working with INFORMIX Online Version 7.10.
Our students are using dbaccess for exercises on SQL.
We found out that a query like :
SELECT first_name, last_name, address
FROM customers
WHERE "John" IN (first_name);
which is clearly syntacticly incorrect (but students try out such things),
does NOT result in a 'syntax error'.
Instead, the server goes down, reporting in "online.log" (the user name is
changed):
10:20:50 Assert Failed: Internal Error - Segmentation Violation
10:20:50 Who: Session(20, name@server, 15722, 5)
Thread(44, sqlexec, a0ff514, 1)
10:20:50 Results: OnLine must abort
10:20:50 Action: Reinitialize shared memory
10:20:50 See Also: /tmp/af.9cba41, shmem.9cba41.0
10:20:51 rsdebug.c, line 3591, thread 44, proc id 23155, Segmentation
Violation.
10:20:51 PANIC: Attempting to bring system down
In my opinion, no possible input for a query (correct or incorrect) should
be able to bring down the database server, especially when executed from
within dbaccess (one of informix' own database tools).
These are (some of) my questions:
- Have others experienced the same problem ?
- Is this a known bug ? (Note that the log file always refers to :
'rsdebug.c', line 3591.)
- Is this problem solved in later versions of the product ?
- Are there any workarounds, except not trying such queries ?
- Are there other "look-like" SQL-queries known to bring down the system ?
Thanks.
---------------------------------------------------------------
Bart Van der Cruyssen Bart.VanderCruyssen@rug.ac.be
UNIVERSITY OF GHENT (BELGIUM) - Computer Science Laboratory
Sint-Pietersnieuwstraat 41, B-9000 GHENT, BELGIUM
tel: +32/9/264.42.23 fax: +32/9/264.42.77