April 2009 - users-list

[MonetDB-users] COPY INTO with dates
by gsd 23 Apr '09

23 Apr '09

Hello, I'm looking into the COPY INTO bulk insert functionality but was wondering how I should format DATEs and TIMESTAMPs? Thanks, Scott -- View this message in context: http://www.nabble.com/COPY-INTO-with-dates-tp23194496p23194496.html Sent from the monetdb-users mailing list archive at Nabble.com.

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Re: [MonetDB-users] Tweaking performance
by Martin Kersten 23 Apr '09

23 Apr '09

Garrett Smith wrote: > 123456789012345678901234567890123456789012345678901234567890123456789012 > > Does anyone have some guidance on approaches for optimizing database > performance? > > I realize this is a pretty broad question :) > > More specifically, I'm running a simple query > > select max(date) from metric > > on a table with 21 million rows (or whatever you call them in Monet). > It's taking quite a bit longer than I'd expect, given a typically > indexed column. Given the fact that there is no (b-tree) index, the underlying engine has to perform a scan to find the maximum. This entails a linear scan over 21M elements in the current implementation. > > On an "explain" I see that there's no difference between the plan with > or without the presence of an index on 'date'. Per the SQL index docs, I > see that indexes are more of a hint to Monet and they're often ignored. > > Cool. > > But what happens when I want to fix what seems to be a configuration > problem with my database/schema? > > Thanks! > > Garrett > > ------------------------------------------------------------------------------ > Stay on top of everything new and different, both inside and > around Java (TM) technology - register by April 22, and save > $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. > 300 plus technical and hands-on sessions. Register today. > Use priority code J9JMT32. http://p.sf.net/sfu/p > _______________________________________________ > MonetDB-users mailing list > MonetDB-users(a)lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/monetdb-users

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[MonetDB-users] Tweaking performance
by Garrett Smith 22 Apr '09

22 Apr '09

123456789012345678901234567890123456789012345678901234567890123456789012 Does anyone have some guidance on approaches for optimizing database performance? I realize this is a pretty broad question :) More specifically, I'm running a simple query select max(date) from metric on a table with 21 million rows (or whatever you call them in Monet). It's taking quite a bit longer than I'd expect, given a typically indexed column. On an "explain" I see that there's no difference between the plan with or without the presence of an index on 'date'. Per the SQL index docs, I see that indexes are more of a hint to Monet and they're often ignored. Cool. But what happens when I want to fix what seems to be a configuration problem with my database/schema? Thanks! Garrett

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Re: [MonetDB-users] the x100 project
by Peter Boncz 20 Apr '09

20 Apr '09

Hi Tom, Thanks for your interest in X100. The project is very much alive in a recent CWI spin-off company called vectorwise. X100 is currently being developed into a fully functional database engine that will fly in datawarehousing and BI environments. Much more than that I cannot say about it now. More news will follow, certainly within a year. It is not yet open source (but in a future that is not off the cards), but if you need that now, you could try MonetDB. Peter > Hello, > I have been asked to evaluate MonetDB. We have interest in the x100 project, is this project still on going... is there a download for it? If > not, is there a plan to release it? > > thanks > tom

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[MonetDB-users] monetdb-client ubuntu package missing binary ?
by Franck Routier 18 Apr '09

18 Apr '09

Hi, I have tried to install and test monetdb using ubuntu repository. But when it comes to using mclient, no binary seems to be installed. Indeed, looking at the package, there seems to be only docs in it. So, am I looking at the wrong place and missing some obvious point, or is the package broken ? (notice that the debian package seems to be similar) Thanks, Franck

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[MonetDB-users] the x100 project
by tom edgar 16 Apr '09

16 Apr '09

Hello, I have been asked to evaluate MonetDB. We have interest in the x100 project, is this project still on going... is there a download for it? If not, is there a plan to release it? thanks tom

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[MonetDB-users] loading big table
by dariuszs 16 Apr '09

16 Apr '09

Hi, I've got a table with 130 fields. When I load 130 million records into that table (about 50G) - it's not a problem, but when I try to load 160 million records (about 60G of data) into it this thing just sits for hours with no error messages. Can somebody help me? Thanks. Dariusz.

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[MonetDB-users] MonetDB XQuery in Production
by Max Fedorov 14 Apr '09

14 Apr '09

The product looks very promising on paper, although not that many people are talking about it and I came across MonetDB by accident. Is anyone using MonetDB in production? Is the product stable enough? I do not feel like spending lots of time testing this XQuery server if nobody runs it in production. I loaded several million records and tested sample queries without issues for the most part, but then once the server just vanished (running latest 32bit version on WindowsXP). I restarted and everything is working again, but now I am very scared. Nothing like this ever happened when using MySQL, MS SQL Server or Oracle. Nothing ever just dies without a trace. Thank you. -Max

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[MonetDB-users] timer option in monetdb
by Mayank Maheshwari 14 Apr '09

14 Apr '09

Hi, I'm working on a project comparing the performance of column-store database systems using MonetDB with the common row-stores for different query scenarios. While running the --timer option on monetDB, I was wondering if it includes the time for printing the result and any other I/O time as well. I'm trying to get the break-up of where the system spends its time while processing the query. Is there a way I could find that out? Also is it possible to find out whats the compression scheme the database is using to store the data? I'm storing a 1 million row table with 6 attributes. Thanks. Mayank Maheshwari mayank(a)cs.wisc.edu

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[MonetDB-users] Fast Loading
by Alex Bo. 14 Apr '09

14 Apr '09

Hi, I came across chapter 3.2.8 in the documentation regarding 'Fast Loading'. I am trying to use it in order to improve the performance I get compared to loading tables using 'COPY INTO'. However, I am not sure how to approach this: "Each file is produced by a program that writes the binary image of the BAT directly, i.e. a binary dump of an C-array" How exactly can I produce these binary images from my source columns? How exactly are they expected by MonetDB to look like? A little more info could be very helpful. Thanks. -- View this message in context: http://www.nabble.com/Fast-Loading-tp23009932p23009932.html Sent from the monetdb-users mailing list archive at Nabble.com.

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