June 2010 - users-list

[MonetDB-users] Meaning of: Scenario not initialized 'sql'
by Alex Bo. 17 Jun '10

17 Jun '10

Hi, Sometimes I get !MALException:setScenario:Scenario not initialized 'sql' from the server when I try to start it in scenarios that usually work without any problems. I can't reproduce it consistently, but sometimes I get it. What does this exception mean? Thanks. -- View this message in context: http://www.nabble.com/Meaning-of%3A-Scenario-not-initialized-%27sql%27-tp26… Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] MonetDB XML - slow execution of query with test on attribute
by Patrick Schäfer 15 Jun '10

15 Jun '10

Hi, I am trying to write a xquery-expression that does a test on an attribute (id="1"). Unfortunately the query execution time for this query is really bad (>30 seconds). Is there any way to find out why this query takes so long? 30 seconds for a test on one single attribute is just way to high for our use-case. I read that MonetDB automatically creates indices on all attribute - is there a way to test, if there was an index created for that attribute and if that index was used for query execution? The query (in File q3.xp) is supposed to return the molecule with id "1" declare namespace xq="http://www.xml-cml.org/schema"; <smiles> { for $i in collection("tu") where $i/xq:molecule/@id = "1" return <smile>{$i}</smile> } </smiles> The query is executed like this: # mclient -t -lx -G q3.xp ... Trans 55.684 msec Shred 18.818 msec Query 29335.766 msec Print 0.258 msec The database contains 1.000.000 XML-documents in a single collection, is updatable and is about 2601 MiB. A document looks similar to this one: <?xml version="1.0" encoding="UTF-8"?> <molecule id="1" xmlns="http://www.xml-cml.org/schema"> <bondArray atomRef1="..." order="..."/> <atomArray atomID="..." elementType="..." x3="..."/> <identifier convention="iupac:smile" value="..."/> <identifier convention="iupac:inchi" value="..."/> </molecule> We are using: "MonetDB/XQuery 0.36.5, based on the pathfinder <http://www.pathfinder-xquery.org> compiler and MonetDB 4.36.1 <http://monetdb.cwi.nl>" Thank you very much for any help! Patrick

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[MonetDB-users] Decimal(p,s)
by Nozhup 15 Jun '10

15 Jun '10

What is the reason that MonetDB only supports a maximum p value of 18 while for example SQL Server (see link) supports up to 38? http://www.w3schools.com/SQL/sql_datatypes.asp -- View this message in context: http://old.nabble.com/Decimal%28p%2Cs%29-tp28892721p28892721.html Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] MIL and GROUP BY
by Hannes Rauhe 14 Jun '10

14 Jun '10

Hello together, I installed MonetDB with the help of the latest monetdb-install.sh and played around with MIL. Now I'm stuck with translating a simple SQL-Query containing a GROUPBY. After starting the server with # Mserver --dbname test --dbinit 'module(mapi); mil_start();' and the client with # ./mclient -lmil -utest -dname=test I tried the following: var a:= bat(oid,int); a.insert(1@0, 1995); a.insert(2@0, 1992); a.insert(3@0, 1993); a.insert(4@0, 1994); a.insert(5@0, 1995); a.insert(6@0, 1996); CTgroup(a).print(); the answer is: ERROR: const operation on a BAT ERROR: CMDconstCopy: operation failed. ERROR: interpret_params: print(param 1): evaluation error. Another try after loading the xtables-Module: mil>module("xtables"); mil>CTgroup(a).print(); +-------------------------------------------------------+ | � | +-------------------------------------------------------+ 1 tuple I used a few papers and http://monetdb.cwi.nl/MonetDB/Version4/Documentation/mil/index.html (Chapter 3.7 is what I'm looking for) as tutorial but didn't find anything helpful. Where's my mistake? Best Regards, Hannes

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[MonetDB-users] Performance degradation
by Michael W Schatzow 11 Jun '10

11 Jun '10

hello, I am having performance degradation issues with repeated queries of monetdb. I am attempting to use monetdb for financial tick data and make sql queries requesting all quotes for a symbol on date x where time > y and time <z. Previously monetdb had worked great for this task and was extremely quick. However, I had a crash last week of the server it was built on. After this monetdb ran incredibly slow on the order of 25 times slower than it was running before. I rebuilt monetdb and it ran quickly for a day or two and started degrading in speed. Could someone give a hint or two on how I should go about debugging this? Is there a optimization task that I need to run? I am really at a loss of how I should handle this. I have been running queries via mclient -s from my program written in python. I previously found the python bindings too slow. Stats: cpu: 2 opteron 2222 os:cent os 5.4 memory 8gb database Size: only testing with csv data of 1.3 GB indexed by date and time built with options:--enable-optimise --enable-sql Thanks for any help, Michael

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[MonetDB-users] libbat.dll crash
by Alex Bo. 09 Jun '10

09 Jun '10

Hi, I am experiencing a consistent Monet crash on an XP 32 bit machine, because of libbat.dll. The exact problem is mentioned here: http://old.nabble.com/--monetdb-Bugs-2982639---Crash-during-server-startup-… However, the link over the there to sourceforge doesn't work, so I can't comment or see what's going on with that bug. I tried it on Aug09-SP1 and Feb2010-SP2 (built from CSV), and both crashed. The link suggest that maybe older Monet dlls are laying around in the system32 folder, but I do not have any of the suggested dlls in there. Any suggestions on this issue? -- View this message in context: http://old.nabble.com/libbat.dll-crash-tp28826934p28826934.html Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] PF/Tijah Question: BM25F?
by jz＠uva 07 Jun '10

07 Jun '10

I was wondering whether it would be possible to use BM25F? http://trec.nist.gov/pubs/trec13/papers/microsoft-cambridge.web.hard.pdf Anyone else tried this before with an XQuery? junte

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