April 2011 - users-list

[MonetDB-users] Series UPDATE statements will significantly decrease server performance
by Vladimir Vlach 13 Apr '11

13 Apr '11

Hi, We are experiencing performance issue with MonetDB when running UPDATE. We have a table with 1M rows and 3.000 columns. All columns except primary_id are FLOAT type. When I execute series of these statements the performance on first 30-35 statements is quite acceptable (less then 1s) but then suddenly it gets really slow. One UPDATE takes 30 seconds or more. After next 5-10 statements the performance decreases and one UPDATE takes 1 minute or longer. We run this with AutoCommit. The behavior is very persistent. UPDATE table SET column=column+1 WHERE primary_id='e1a7d7c7204c292e56e942dbdad118d3' ; Would you say MonetDB is not suitable for bulk UPDATE operations? Thanks, Vlad

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[MonetDB-users] UPDATE INNER JOIN syntax
by Osmin Castillo 11 Apr '11

11 Apr '11

Hi guys: How can I to update a table field based on a inner join update? What's the syntax for MonetDB? thanks in advance Osmin Castillo

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[MonetDB-users] How to recover Database after crash
by Vladimir Vlach 11 Apr '11

11 Apr '11

Hi, is there guide on how to recover DB after server crash? I get following error: root@monetdb:/var/monetdb5/dbfarm# monetdb release vlad_a-f taken database out of maintenance mode: vlad_a-f root@monetdb:/var/monetdb5/dbfarm# monetdb start vlad_a-f starting database 'vlad_a-f'... FAILED start: starting 'vlad_a-f' failed: database 'vlad_a-f' appears to shut itself down after starting, check merovingian's logfile for possible hints root@monetdb:/var/monetdb5/dbfarm# tail /var/log/monetdb/merovingian.log 2011-04-11 11:40:53 MSG merovingian[2477]: starting database 'vlad_a-f', up min/avg/max: 2s/1h/15h, crash average: 0.00 0.30 0.20 (18-12=6) 2011-04-11 11:40:53 MSG vlad_a-f[2783]: arguments: /usr/bin/mserver5 --config=/etc/monetdb5.conf --dbname=vlad_a-f --set merovingian_uri=mapi:monetdb://monetdb:50000/vlad_a-f --set mapi_open=false --set mapi_port=0 --set mapi_usock=/var/monetdb5/dbfarm/vlad_a-f/.mapi.sock --set monet_vault_key=/var/monetdb5/dbfarm/vlad_a-f/.vaultkey --set monet_daemon=yes 2011-04-11 11:40:53 ERR vlad_a-f[2783]: !FATAL: BBPinit: could not write bat/BBP.dir 2011-04-11 11:40:53 MSG merovingian[2477]: database 'vlad_a-f' (2783) has exited with exit status 1 2011-04-11 11:41:02 ERR control[2477]: (local): failed to fork mserver: database 'vlad_a-f' appears to shut itself down after starting, check merovingian's logfile for possible hints Is there a procedure how to recover this? Thanks, Vlad

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[MonetDB-users] Temporary tables
by Charalampos Nikolaou 10 Apr '11

10 Apr '11

Hi, this page (http://monetdb.cwi.nl/SQL/Documentation/Table-Definition.html) states that only the LOCAL TEMPORARY scope of SQL is implemented. Considering the following interaction with in mclient, it does not seem that is implemented at all. Am I missing something here or it is a bug? sql>CREATE LOCAL TEMPORARY TABLE transaction_statements ( ctx INTEGER NOT NULL, subj INTEGER NOT NULL, pred INTEGER NOT NULL, obj INTEGER NOT NULL, expl BOOL NOT NULL ); operation successful sql>INSERT INTO transaction_statements (ctx, subj, pred, obj, expl) VALUES (0, 1, 2, 805306369, 1); 1 affected row (10.450ms) sql>SELECT * FROM transaction_statements; +-----+------+------+-----+------+ | ctx | subj | pred | obj | expl | +=====+======+======+ +-----+------+------+-----+------+ 0 tuples (1.490ms) sql>SELECT * FROM tmp.transaction_statements; +-----+------+------+-----+------+ | ctx | subj | pred | obj | expl | +=====+======+======+ +-----+------+------+-----+------+ 0 tuples (1.443ms) sql>SELECT * FROM tmp._tables; +------+------------------------+------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------+------+-------+------+-------+ | id | name | sche | query | type | syste | comm | reado | : : : ma_i : : : m : it_a : nly : : : : d : : : : ctio : : : : : : : : : n : : +======+========================+======================================================================+======+=======+======+=======+ | 5678 | transaction_statements | 2103 | null | 0 | false | 1 | false | +------+------------------------+------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------+------+-------+------+-------+ 1 tuple (2.013ms) Thanks, Babis

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[MonetDB-users] build failed on undefined crypt references
by Sander Kruseman 10 Apr '11

10 Apr '11

Hi, Building from recent tar.bz2 (11.1.1) on Linux/x86_64 I get: libtool: link: gcc -g -O2 -Wno-declaration-after-statement -D_REENTRANT -o .libs/mclient mclient.o ReadlineTools.o -pthread -Wl,--export-dynamic ./.libs/libmcutil.a ../mapilib/.libs/libmapi.so /var/scratch/sander/MonetDB-11.1.1/common/stream/.libs/libstream.so ../../common/stream/.libs/libstream.so -lbz2 -lreadline -ltermcap -lcrypt -pthread -Wl,-rpath -Wl,/usr/local/lib ../mapilib/.libs/libmapi.so: undefined reference to `MD5' ../mapilib/.libs/libmapi.so: undefined reference to `SHA224' ../mapilib/.libs/libmapi.so: undefined reference to `RIPEMD160' ../mapilib/.libs/libmapi.so: undefined reference to `SHA512' ../mapilib/.libs/libmapi.so: undefined reference to `SHA384' ../mapilib/.libs/libmapi.so: undefined reference to `SHA256' ../mapilib/.libs/libmapi.so: undefined reference to `SHA1' What could be causing this? Any help is much appreciated. Sander Kruseman

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[MonetDB-users] How to access MonetDB in Javascript without XRPC/XQuery?
by dsuh 08 Apr '11

08 Apr '11

Now that XRPC/XQuery is being removed from the MonetDB source, are there any options for client-side browser Javascript access to SQL queries? Would it end up looking like using the PHP interface in the web server side and passing the results to the client-side Javascript? Exactly how would this look like? I am interested in using HTML5/Javascript on the client-side to create a mashup of different data including GIS information from MonetDB. Can anyone suggest possible solutions? David Suh

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[MonetDB-users] history support in mclient across sessions
by Charalampos Nikolaou 07 Apr '11

07 Apr '11

Hi, does mclient support saving of commands in a history file and accessing them again in a future mclient session? Currently, there is a -H option, but it doesn't seem to work (Mar2011 release). Thanks, Babis

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[MonetDB-users] Killing long running queries
by Ramkumarlak 06 Apr '11

06 Apr '11

Is there any way to know the current running queries (like mysql's "show full processlist"). Also is there any way of killing long running queries. -- View this message in context: http://old.nabble.com/Killing-long-running-queries-tp31276295p31276295.html Sent from the monetdb-users mailing list archive at Nabble.com.

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Re: [MonetDB-users] [expath] Kudos on CXAN
by Christian Grün 04 Apr '11

04 Apr '11

…time for MonetDB to join up ;) ___________________________ On Tue, Apr 5, 2011 at 12:04 AM, Florent Georges <fgeorges(a)gmail.com> wrote: > On 3 April 2011 14:31, Chris Maloney wrote: > >> Florent, I suddenly realized this morning why you have the >> image that you do on the CXAN site -- it's a pronunciation >> hint! > > Good catch! > > For the others, the picture on the home page of CXAN > <http://cxan.org/beta/> is a painting of Paul Cezanne > <http://en.wikipedia.org/wiki/Paul_C%C3%A9zanne>, a French > painter. > > I hesitated with a self-portrait (this one is a portrait of > Victor Chocquet, dont ask me who he is), but I liked this one. > The hint is that the X is actually pronounced like a Z, to make > the name fluent (either a la French, with a C like in sailer, or > English style, with a C like in sea). > > Very good catch :-) > > -- > Florent Georges > http://fgeorges.org/ > > -- > You received this message because you are subscribed to the Google Groups "EXPath" group. > To post to this group, send email to expath(a)googlegroups.com. > To unsubscribe from this group, send email to expath+unsubscribe(a)googlegroups.com. > For more options, visit this group at http://groups.google.com/group/expath?hl=en.

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[MonetDB-users] query dit not produce result set
by Bas Kaptijn 04 Apr '11

04 Apr '11

Hi, with the MAR2010 release (x64 windows through installer) (and also the release Feb2010-SP2) I get an exception running a particular query, whilst a slightly modified one with the expected result (except for the naming of a result column) does not. I narrowed the problem down to this: sql>CREATE TABLE dbg (a INT, b INT); operation successful sql>INSERT INTO dbg (a,b) VALUES (10,10); 1 affected row (32.410ms) sql>SELECT a as d, SUM(b), (2 * (SUM(b) / (SELECT 2))) as f FROM dbg GROUP BY d; +------+------+------+ | d | L451 | f | +======+======+======+ | 10 | 10 | 10 | +------+------+------+ 1 tuple (8.841ms) sql>SELECT a as d, SUM(b) as e, (2 * (SUM(b) / (SELECT 2))) as f FROM dbg GROUP BY d; sql> The second select query does not produce a result set (as stated in the SQLException I get when doing this through JDBC). The monetdb client just shows a new prompt without stating any warning/error. The query works when I remove the "as e" ... or the "select 2" but in the real case I get this problem this select does much more than just selecting the number 2. I think this is a bug. Or am I doing something that is not (yet) supported in MonetDB? Thanks Bas Kaptijn

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