March 2015 - users-list

Geometrical grid for spherical data
by Jiří Nádvorník 17 Mar '15

17 Mar '15

Hi All, I have spherical coordinates (right ascension, declination) and I'd like to iterate over areas in this 2-dimensional space. Easiest that comes to mind is just create a grid of squares (say 5 arcsecs wide) and iterate over them. Is it easier to do this in MonetDB with just spherical coordinates (some kind of spherical index), or do I have to convert them to x,y,z coordinates and create the grid in 3D? Thank you for your insight. Jiri Nadvornik Astronomical Institute AV … [View More]

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Discussion on Concurrency Insert Issue "insert into A from B table and insert into C from D "
by Shivanandan Gupta 17 Mar '15

17 Mar '15

Hi All, I have written a java program when runs a two threads in parallel , copy command in parallel is working fine using batch files but the insert into using batch file is getting hanged , I have given the commands below which I have used in the batch file. Copy command Batch. mclient.bat demo -s "copy into A FROM 'D:\ETL_Source\abcd.csv' using delimiters ',';" Insert into Batch mclient.bat demo -s "insert into B select * from A;" One more problem I am facing is that while running … [View More]

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Multi threaded (2 threads) Java program for copy command
by Shivanandan Gupta 13 Mar '15

13 Mar '15

Hi Jennie, I am getting below given exception while running in parallel. Exception in thread "main" java.sql.SQLException: COMMIT: transaction is aborted because of concurency conflicts, will ROLLBACK instead at nl.cwi.monetdb.jdbc.MonetConnection$ResponseList.executeQuery(MonetConnection.java:2535) at nl.cwi.monetdb.jdbc.MonetConnection$ResponseList.processQuery(MonetConnection.java:2284) at nl.cwi.monetdb.jdbc.MonetStatement.internalExecute(MonetStatement.java:508) at nl.cwi.monetdb.jdbc.… [View More]MonetStatement.execute(MonetStatement.java:349) at connect_monetdb.runETL2(connect_monetdb.java:79) at connect_monetdb.main(connect_monetdb.java:14) Thank you, Shivanandan Gupta. On Fri, Mar 13, 2015 at 8:09 PM, Shivanandan Gupta < shivnandangupta(a)gmail.com> wrote: > Hi Jennie, > > Thanks for your reply. please find my replies below: > > Jennie Commented: Concurrent insertion into two different tables should > work. Do you have anymore information about why the COMMIT has failed? > Maybe the problem lies somewhere else than concurrent insertions? > > Shiva's Comment: yes when I run two batch file by clicking it with > difference of second ( as it takes few seconds to click the second batch > file) and it runs perfectly, even I have tried running copy command > directly on the monetsql client and on two clients in parallel it works > perfectly. Is there some configuration change required on monetdb server? > > Jennie Commented: - Have you tried the two COPY INTO separately? To know > if the problem is indeed caused by concurrent insertions. > > Shiva's Comment: When I am trying with two separate java program running > concurrently its throwing same exception. > > > Jennie Comment: - Does the problem occur one-time, or every time you > repeatedly execute your code? > Shiva's Comment: Yes the same error message is coming every time I run > concurrent java programs with copy command in it ( here copying data to > different tables ). > > Any help will be really appreciated. > > Thank you. > > Shivanandan Gupta. > > > Date: Fri, 13 Mar 2015 15:36:23 +0800 > From: Ying Zhang <Y.Zhang(a)cwi.nl> > To: Communication channel for MonetDB users <users-list(a)monetdb.org> > Cc: martin(a)monetdb.org > Subject: Re: Multi threaded (2 threads) Java program for copy command > Message-ID: <89A66109-B083-45A4-B59E-62B7AF0C9D86(a)cwi.nl> > Content-Type: text/plain; charset=us-ascii > > > > On Mar 12, 2015, at 19:27, Shivanandan Gupta <shivnandangupta(a)gmail.com> > wrote: > > > > Hi Martin, > > > > Thanks for your prompt reply , I am using two different tables here but > still I am getting "Exception in thread "main" java.sql.SQLException: > COMMIT: failed" exception. > > Hello Shivanandan, > > Concurrent insertion into two different tables should work. Do you have > anymore information about why the COMMIT has failed? Maybe the problem > lies somewhere else than concurrent insertions? > > - Have you tried the two COPY INTO separately? To know if the problem is > indeed caused by concurrent insertions. > - Does the problem occur one-time, or every time you repeatedly execute > your code? > > Regards, > > Jennie > > > > On Thu, Mar 12, 2015 at 4:57 PM, Shivanandan Gupta < > shivnandangupta(a)gmail.com> wrote: > >> Hi Martin, >>> >> >> Thanks for your prompt reply , I am using two different tables here but >> still I am getting "Exception in thread "main" java.sql.SQLException: >> COMMIT: failed" exception. >> >> >> >>> Message: 2 >>> Date: Thu, 12 Mar 2015 08:32:31 +0100 >>> From: Martin Kersten <martin(a)monetdb.org> >>> To: users-list(a)monetdb.org >>> Subject: Re: Multi threaded (2 threads) Java program for copy command >>> commit fails for one thread >>> Message-ID: <5501410F.1070508(a)monetdb.org> >>> Content-Type: text/plain; charset=windows-1252; format=flowed >>> >>> Hi, >>> >>> Yes. Insertion into the same table would be invalidated due to the >>> transaction semantics. >>> See >>> https://www.monetdb.org/Documentation/Manuals/SQLreference/Transactions >>> >>> [View Less]

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Re: Multi threaded (2 threads) Java program for copy command
by Shivanandan Gupta 13 Mar '15

13 Mar '15

> > Hi Martin, > Thanks for your prompt reply , I am using two different tables here but still I am getting "Exception in thread "main" java.sql.SQLException: COMMIT: failed" exception. > Message: 2 > Date: Thu, 12 Mar 2015 08:32:31 +0100 > From: Martin Kersten <martin(a)monetdb.org> > To: users-list(a)monetdb.org > Subject: Re: Multi threaded (2 threads) Java program for copy command > commit fails for one thread > Message-ID: <5501410F.… [View More]

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Multi threaded (2 threads) Java program for copy command commit fails for one thread
by Shivanandan Gupta 12 Mar '15

12 Mar '15

Hi All, I am evaluating monetdb for our dwh and I am trying to load data from two different csv file to 2 different tables using multi-threaded java program in parallel, for one thread the load is successful and other one is failing with exception given below. Exception in thread "main" java.sql.SQLException: COMMIT: failed at nl.cwi.monetdb.jdbc.MonetConnection$ResponseList.executeQuery(MonetConnection.java:2535) at nl.cwi.monetdb.jdbc.MonetConnection$ResponseList.processQuery(… [View More]

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Re: Problem with Datacell
by Julien Marie 10 Mar '15

10 Mar '15

I managed to make it work a bit more by installing Jan-2014 version of MonetDB. I can send data into datacell, I can send data out of datacell if I insert directly into the bsktout. But the queries are not working : +----------------+---------+---------------------------+--------+------+----------+----------------------------+----------------------------+ | nme | status | lastrun | cycles | even | time | error | def … [View More]

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Horizontal partitioning
by Bart Lenoir 09 Mar '15

09 Mar '15

Hi All, Does MonetDB besides load balancing (round robin) in its clustering also support horizontal partitioning? If so, how? Thanks. Cheers, John

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Problem with Datacell
by Julien Marie 09 Mar '15

09 Mar '15

I know the feature is deemed experimental, but I have troubles just to start the example and I keep on having transaction error messages : sql>call datacell.receptor('datacell.bsktin', 'localhost', 50500); sql>call datacell.emitter('datacell.bsktout', 'localhost', 50600); START TRANSACTION: cannot start a transaction within a transaction What is going on ? Thank you very much -- *Julien Marie* jm(a)producture.com skype : thewiseup +63 917 511 8258 -----BEGIN PGP PUBLIC KEY BLOCK-… [View More]

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Clustering
by Jiří Nádvorník 03 Mar '15

03 Mar '15

Hi All, I'm trying to solve a clustering problem on my astronomical data. It is simply repeated observations of stars on images with random errors, effectively creating clusters with Gaussian distributions. These clusters have from 1 to cca 1000 points and are approximately of the same size (~1 arcsec). So much for the introduction. I already tried to solve this problem with simple methods but with poor results. Our regions are very dense and the size of the clusters is often (cca 20 % … [View More]

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Converting Bigint field (containing unixtime in millisecs) to TIMESTAMP
by Davide Magatti 02 Mar '15

02 Mar '15

Hi all, Database: MonetDB v11.19.9 (Oct2014-SP2) I am trying to convert a big string fiel in a table containing unixtimes in millisecs to timestamps but i cannot find the right way to do it. So my table descriptor: TABLE "table" ( "user" VARCHAR(512), "time" BIGINT, [...] ); i tried to do > select CAST( CAST(time/1000 AS INTERVAL SECOND) AS TIMESTAMP) from table ; >>types sec_interval(13,0) and timestamp(7,0) are not equal And did not work, also using time in … [View More]

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