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About database crack
by chenkaijiang＠bigknow.com.cn 06 Jan '16

06 Jan '16

Hi, all, I find that in Oct2010 branch (http://dev.monetdb.org/hg/MonetDB/shortlog/Oct2010) it looks like that the database cracking technology has been implemented. But looks like that it wasn't merged into the latest release (Jul2015), right? Why not merge this into the latest release? Is there any plan to merge it in the future?

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MonetDBLite error in R
by Iain Wallace 06 Jan '16

06 Jan '16

hi all, I was wondering if anybody could suggest how to debug this error: Server says 'GDKerror:!ERROR: BATsetaccess: tmp_3505 has -1 views I am trying to do a simple join using dplyr sample%>%left_join(interaction_pairs) The tables appear to be working correctly as I can collect them and use them in R properly interaction_pairs<-collect(interaction_pairs) Thanks Iain

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invalid credentials using mserver5
by Xu,Wenjian 06 Jan '16

06 Jan '16

Hi all, Normally I am using *monetdbd*+"mclient" combination to use MonetDB. Now, since I want to see the debug info in each gdk operator, I have to use *mserver5*. I do as follows (JULY2015-SP1+ubuntu14.04): Step1: $ mserver5 --dbpath=${HOME}/[my_dbpath] --daemon=yes --algorithms Step2: In another console: $ mclient -d [dbname] -u monetdb password: monetdb It replies: InvalidCredentialsException:checkCredentials:invalid credentials for user 'monetdb' However, user:monetdb, pwd:monetdb is the default one and I can use it successfully in *monetdbd*+"mclient" combination. Any idea? Thanks, XU Wenjian

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Jdbc Driver
by Luciano Sasso 05 Jan '16

05 Jan '16

Hi, Its error "https://www.monetdb.org/bugzilla/show_bug.cgi?id=3561", persist in version 2.19, exists most new version with bug fix ? -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano(a)gsgroup.com.br <http://www.gsgroup.com.br> | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br <http://www.gsgroup.com.br> --- Este email foi escaneado pelo Avast antivírus. https://www.avast.com/antivirus

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Dropping foreign key constraint
by Alexander Gordt 04 Jan '16

04 Jan '16

Hello together, I’m very new to MonetDB, so please be gracious :) I’m trying to drop a foreign key, what should be a very simple task – but I didn’t manage to do it. The following statement ran successfully – as the result says – but the foreign key is still there: alter table visit drop constraint visit_configuration_id_fkey; I also tried this – but this command is not supported?? alter table visit drop foreign key visit_configuration_id_fkey; An error occurred when executing the SQL command: alter table visit drop foreign key visit_configuration_id_fkey syntax error, unexpected FOREIGN in: "alter table visit drop foreign" [SQL State=42000] Execution time: 0.01s 1 statement failed. Best regards and thanks for any hints, Alex

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could == be aliased to the = operator? or will that break things?
by Anthony Damico 04 Jan '16

04 Jan '16

hello, just an idea-- if monetdb gets a flood of new R users over the next year, they might get thrown off by things breaking when they use a double-equals sign (example below).. sqlite accepts the double-equals as a single equals. thanks > dbGetQuery(db,'select count(distinct mycolumn) from mytable where yr=2003') L1 1 334343 > dbGetQuery(db,'select count(distinct mycolumn) from mytable where yr==2003') Error in .local(conn, statement, ...) : Unable to execute statement 'select count(distinct mycolumn) from mytable where yr==2003'. Server says 'syntax error, unexpected '=' in: "select count(distinct mycolumn) from mytable where yr=="' [#42000]. >

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Re: Update: Extract Table Statistics after Data import using Monet.Read.Csv
by Anthony Damico 31 Dec '15

31 Dec '15

https://www.monetdb.org/bugzilla/show_bug.cgi?id=3835 next version release should fix this.. or use monetdblite which already has the fix (the example scripts i sent use monetdblite) On Dec 30, 2015 11:53 PM, "Jigar Shah" <jigar.shah1984(a)hotmail.com> wrote: > Thanks a lot Dr. Hannes, Anthony. The trick worked perfectly. See the > stats below: > > > > > > However, there is one odd behavior I have noticed. Even after completion > of the query, the RAM usage is still the same as when running the query. > The RAM usage only reduces once I terminate the connection and stop the > server. > > Is this behavior normal for the MonetDB server ? Also, ‘Src_MonetDB’ > creates a separate connection than ‘dbConnect’ > > Can the two connection run at the same time ? I noticed that sometimes > when I use the Src_MonetDB connection, the dbConnect gets terminated > automatically. > > Thanks a lot for your help on these. > > Best Regards, > > Jigar > > Sent from Mail <http://go.microsoft.com/fwlink/?LinkId=550986> for > Windows 10 > > > > > *From: *Anthony Damico <ajdamico(a)gmail.com> > *Sent: *Tuesday, December 29, 2015 6:22 AM > *To: *Communication channel for MonetDB users <users-list(a)monetdb.org> > *Subject: *Re: Extract Table Statistics after Data import using > Monet.Read.Csv > > > > for an example of this, see > > > https://github.com/ajdamico/asdfree/tree/master/Basic%20Stand%20Alone%20Med… > > On Dec 29, 2015 2:50 AM, "Hannes Mühleisen" <hannes.muehleisen(a)cwi.nl> > wrote: > > Hi Jigar, > > > On 29.12.2015, at 01:21, Jigar Shah <jigar.shah1984(a)hotmail.com> wrote: > > > > The dataset is divided into have 12 tables of approx. 2 GB each. In > order to recreate the entire dataset, I want to use the MERGE function to > merge all the 12 tables into one dataset for further analysis. > > > You can pass a vector of _all_ your file names to monetdb.read.csv(), this > will load all of them into a new table and does not require the merge. The > different schemas come from the function guessing the column types from the > file. > > Hannes > > _______________________________________________ > users-list mailing list > users-list(a)monetdb.org > https://www.monetdb.org/mailman/listinfo/users-list > > >

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Performing a direct access to MonetDB's BAT tables via MAL
by Giacomo Bergami 31 Dec '15

31 Dec '15

Good Morning/Evening everyone. My aim is to direcly access to the BAT column store representation of MonetDB through the standard libraries (MAPI/JDBC) - if possible. I know that each SQL query gets rewrited into a BAT algebra expression, but in my case I want to access to a single value per time (e.g. I want to access to the value stored in the i-th row and in the column labelled "j" of a given table) and maybe in this case the direct access is quicker than performing the whole SQL query. I've already tried to use the mclient with the MAL language and read the documentation, and I tried to use the client with something like this: mdb.start(); bbp.open(); bbp.prelude(); a := bbp.bind("fx", "size"); where "fx" should be the name of the table and "size" one of its attributes. But unfortunately I do not know how to search for a specific row-key and to get the correspondant value, and AFAIK i have to get the id of the column "size". Thanks in advance, Giacomo Bergami ____________________________ Giacomo Bergami, Ph.D Student University of Bologna https://www.unibo.it/sitoweb/giacomo.bergami2

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Almost all test cases failed in "sql" package
by Xu,Wenjian 31 Dec '15

31 Dec '15

Hi, I have compiled and installed MonetDB-11.21.11 (JUL2015-SP1) from pre-packaged source distribution. My environment is Ubuntu 14.04 LTS. I tried to run the test cases by the following command: $ sudo Mtest.py -r [package-name] I found that almost all tests PASSED when [package-name]=monetdb5, which is expected. But when I switched to [package-name]=sql, almost all tests FAILED. What is the reason? Or I did something wrong? Any idea would be helpful. Thanks. Best, Wenjian

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回复：Is there any MonetDB branch that supports B-tree index?
by chenkaijiang＠bigknow.com.cn 30 Dec '15

30 Dec '15

The lecture can also be found at http://homepages.cwi.nl/~manegold/teaching/adt/lectures/lecture5.pdf ----- 原始邮件 ----- 发件人：<chenkaijiang(a)bigknow.com.cn> 收件人：users-list<users-list(a)monetdb.org> 主题：Is there any MonetDB branch that supports B-tree index? 日期：2015-12-30 23:46:03 Hi, all, from page 2 of the attach lecture5.pdf, it looks like that MonetDB supports B-tree index in some branch? Is there any MonetDB branch that supports B-tree index? (I mean the persistent index that can be used in a query without creating it on the fly) Regards,Kaijiang

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