Bugs item #2183288, was opened at 2008-10-21 00:57
Message generated for change (Comment added) made by skinkie
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=482468&aid=2183288&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: SQL CVS Head
Status: Closed
Resolution: Fixed
Priority: 5
Private: No
Submitted By: Stefan de Konink (skinkie)
Assigned to: Niels Nes (nielsnes)
Summary: SQL: no error about invalid *qualified* column name
Initial Comment:
I find many errors that I reported here were based on my incompetence to
remember field names, and the use invalid fieldnames. Would it be possible to
warn a user if a comparison is done on a field that does not exist in the
table, nor is a variable?
Example, I type:
SELECT * FROM way_tags WHERE waysid = 100;
In this table the field waysid does not exist, and the query will also return 0
tuples.
If we advance to a query where this wrong field is used in a comparison with
another field that doesn't exist hence:
select * from way_tags as w1, way_tags as w2 where w1.k = 'bridge' and w1.wayid
= w2.wayid;
Unexpected behavior occurs.
Now I don't know if this is a bug, or actually a valid principle according to
SQL. But if two features on their own return 0 tuples simple because the
feature doesn't exist, shouldn't the query at least directly return 0, warn (or
better abort!) if such thing is located. I plea guilty, fully, but there are
users that like my don't have the precision of working with MonetDB and are
rather 'verstrooid'.
----------------------------------------------------------------------
Comment By: Stefan de Konink (skinkie)
Date: 2008-10-21 18:54
Message:
Niels, thanks for fixing it.
@Stefan:
"The difference is most probably related to giving only an attribute name
vs. giving <table_name>.<attribute_name> ..."
I think you found something out that I was not mentally aware of at the
time of 'seeing' this bug, fundamentally you already knew what was wrong.
With mentioning 'unexpected behavior occurs' I was not aware of it.
----------------------------------------------------------------------
Comment By: Stefan Manegold (stmane)
Date: 2008-10-21 15:53
Message:
Fixed by Niels in CVS.
Thanks for the quick fix, Niels!
----------------------------------------------------------------------
Comment By: Stefan Manegold (stmane)
Date: 2008-10-21 14:11
Message:
for got this in my previous posting below:
sql>create table t (a integer);
0 tuples
(ps: see my previous posting below as an example how to file a proper
useful bug report including minimal instructions to fully reproduce the
problem and information about where the problem occurs --- any (successful)
attempt to learn from that would be highly appreciated...)
----------------------------------------------------------------------
Comment By: Stefan Manegold (stmane)
Date: 2008-10-21 14:06
Message:
While MonetDB/SQL correctly issued an error when trying to use a
non-existing unqualified column name, it seems to fail to do so in case of
non-existing qualified column names:
(with CVS HEAD of Tue Oct 21 09:19:22 CEST 2008, configured with defaults,
compiled with gcc 4.1.2 on 64-bit Fedora 8)
sql>select * from t where b = 0;
!SELECT: identifier 'b' unknown
0 tuples
sql>select * from t where t.b = 0;
0 tuples
sql>select * from t where s.a = 0;
!SELECT: no such column 's.a'
0 tuples
----------------------------------------------------------------------
Comment By: Stefan Manegold (stmane)
Date: 2008-10-21 13:57
Message:
Ah, here's the actual problem (and I actually consider this a bug):
With
sql>create table way_tags (way integer);
0 tuples
query
sql>SELECT * FROM way_tags WHERE waysid = 100;
^^^^^^
!SELECT: identifier 'waysid' unknown
0 tuples
correctly issues an error,
query
sql>SELECT * FROM way_tags WHERE way_tags.waysid = 100;
^^^^^^^^^^^^^^^
0 tuples
does not.
The difference is most probably related to giving only an attribute name
vs. giving <table_name>.<attribute_name> ...
----------------------------------------------------------------------
Comment By: Stefan Manegold (stmane)
Date: 2008-10-21 13:48
Message:
works for me (CVS head of Tue Oct 21 09:19:22 CEST 2008):
sql>create table way_tags (way integer);
0 tuples
sql>SELECT * FROM way_tags WHERE waysid = 100;
!SELECT: identifier 'waysid' unknown
0 tuples
----------------------------------------------------------------------
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=482468&aid=2183288&group_id=56967
-------------------------------------------------------------------------
This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
http://moblin-contest.org/redirect.php?banner_id=100&url=/
_______________________________________________
Monetdb-bugs mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/monetdb-bugs
