June 2015 - users-list

[MonetDB-users] Books CDs
by CHARTS LICENSING 11 Aug '24

11 Aug '24

Everything you want to know this dynamic artist check. At blueberry hills duck, roomfull story gtgt getting. Intriguing, life in biography. Here music looking for lyrics maybe, youre find which! Download free wallpapers featuring business cmg worldwide is exclusive. Videos latest products been easier. Exclusive estate we consider request use name voice, image. List covered berries charts licensing message! Reelin and rockin about, has everything you? Many exciting, photos him stage click! Artist check, out some quotes read all intriguing. It alive he, did on occasion birthday wednesday? Has everything you want to know this? Quotes read all intriguing life, in biography or. Gtgt getting licks years reelin and. Click here, music looking for lyrics maybe, youre. News celebrates his th rock will never! Chuck berry news celebrates his th rock, will. Browse through many exciting, photos him stage click here. He did on occasion birthday wednesday night at blueberry. Wallpapers featuring business cmg worldwide. Worldwide is exclusive estate we consider, request use name. Want to know this dynamic artist check out. Awards fast, facts clips list covered. Music looking for lyrics maybe youre. Message board downloads tour dates fan, club inquiries. Other sites, download free wallpapers featuring, business cmg worldwide. Request use, name, voice.

2 1

Multi-column update based on joined table
by Lee Hachadoorian 11 Aug '24

11 Aug '24

I need to update multiple columns (~250) from one table to another based on a two-column key. In Postgres I would write this using the FROM clause, but since MonetDB doesn't support the FROM clause, I've successfully updated one column with: UPDATE census.acs2010_5yr SET b07401001 = ( SELECT CAST(b07401001 AS int) FROM acs2010_5yr.tmp_seq0001 WHERE acs2010_5yr.stusab = tmp_seq0001.stusab AND acs2010_5yr.logrecno = tmp_seq0001.logrecno ); My question is whether there is any benefit to writing a multiple column update into a single UPDATE statement: UPDATE target_table SET column1 = (SELECT column1 FROM source_table WHERE target_table.key = source_table.key), column2 = (SELECT column2 FROM source_table WHERE target_table.key = source_table.key), ..., columnN = (SELECT columnN FROM source_table WHERE target_table.key = source_table.key); On Postgres I believe the multi-column update using a table join would only have to do the sequential scan of each table once, but with the necessity of sub-selects in MonetDB, what is the backend doing? Is it already doing an index scan once for each row in the single column case, then doing it once for each row * column in the multi-column case? Best, --Lee -- Lee Hachadoorian Asst Professor of Geography, Dartmouth College http://freecity.commons.gc.cuny.edu/

3 3

[MonetDB-users] XQuery API and XLink/XUpdate support
by Alexandra Mart�nez 27 Jun '24

27 Jun '24

Hello all, I was wondering if there is any documentation about the API for XQuery (i.e., how to write xqueries from a Java program). Also, I am interested in using some features of XLink and XUpdate on top of my XML database. Is support for any of these in progress? Thanks in advance, Alexandra ______________________________________________________ Click here to donate to the Hurricane Katrina relief effort. http://store.yahoo.com/redcross-donate3/

4 3

[MonetDB-users] Proofreading your professional documents
by Richard Hounslow 24 Feb '24

24 Feb '24

Dear Professor/Lecturer Please excuse us for contacting you directly. We are offering an efficient service to help you ensure your academic and professional work is written in perfect English. We will check the grammar and style of your work and return it to you to meet your requirements and deadlines. Proof-Reading-Service.com can provide you with a professional proofreading service at a very reasonable rate. All our proofreaders are highly qualified native English speakers. Many work as leading academics in their fields and all have extensive experience of proofreading to the highest standards. If you are interested in our service, please take a look at our website: www.proof-reading-service.com All you have to do is send us your document as a word attachment with the deadline and we will guarantee delivery of a perfectly written document to give you complete confidence when you submit your work. The fee is worked out on a flat rate (£6.95 per thousand words or 0.695 pence per word), so you know exactly how much the proofreading will cost in advance. Once we have received your document(s) we will confirm the word count, the price and the deadline. If you have not heard from us within 2 hours during normal business hours after you have sent your work please resend it from a different email account or send the file to proofreadings(a)gmail.com. We look forward to hearing from you! Yours faithfully Proof-Reading-Service.com

2 2

nearest value question on stackoverflow
by Anthony Damico 17 Jul '15

17 Jul '15

https://stackoverflow.com/questions/30641876/monetdb-sql-method-to-locate-o… i'm thinking i can do this with some costly self-join, but i'd appreciate any other eyes on the problem

4 12

Should MonetDB really be used in production?
by Frédéric Jolliton 16 Jul '15

16 Jul '15

Greetings, We filled a bug few days ago about simple SAVEPOINT usage corrupting the database (both in Oct2014-SP4 and tip of hg). This is worrying us a lot, because that's yet another bug easy to trigger. We're studying MonetDB extensively for our future needs. We've written optimizers, custom aggregate functions in C, and we've studied many internal aspects. But yet, from time to time, we are hit by bugs when performing simple, trivial queries. You can see the history of bugs we filled on the bugtracker (regarding UNION, SELECT, ..). This become time consuming. This make us nervous because we might have hard time trusting our complexes queries run by MonetDB. The performance are stunning, but the quality seems not high enough for production. Projects like PostgreSQL shows that even Open Source projects can attains incredible stability and robustness. (Admittedly there are many more contributors to PostgreSQL.) Note that we understand that it is a complex software, and that it is hard to cover all possible corner cases in tests. But we're wondering how stable MonetDB is expected to be. Is this really used in production? Regarding the MonetDB website, the primary source of information for the project, we've not found any reference documentation regarding all the supported SQL features. Sure, there is a page listing what is *not* supported, there are pages on various topics, but it is unclear if SAVEPOINT is really supported. (If I can say, I think that the website probably needs some refresh and better navigation.) Here is the latest bug I was talking about: $ bin/mclient -p 50005 test Welcome to mclient, the MonetDB/SQL interactive terminal (Oct2014-SP4) Database: MonetDB v11.19.13 (Oct2014-SP4), 'mapi:monetdb://fjolliton:50005/test' Type \q to quit, \? for a list of available commands auto commit mode: on sql>start transaction; auto commit mode: off sql>create table foo (a int); operation successful (0.528ms) sql>savepoint sp1; auto commit mode: off sql>release savepoint sp1; auto commit mode: off sql>commit; auto commit mode: on sql>select * from foo; +---+ | a | +===+ +---+ 0 tuples (0.9s) So far, so good. Now try to connect again: $ bin/mclient -p 50005 test Welcome to mclient, the MonetDB/SQL interactive terminal (Oct2014-SP4) Database: MonetDB v11.19.13 (Oct2014-SP4), 'mapi:monetdb://fjolliton:50005/test' Type \q to quit, \? for a list of available commands auto commit mode: on sql>select * from foo; SELECT: no such table 'foo' Whoops ! Regards, -- Frédéric Jolliton Sécuractive

9 10

Cluster advantages MonetDB
by Luciano Sasso 15 Jul '15

15 Jul '15

Hi, What the cluster Advantages MonetDB, If a query in shard tables in a cluster can not be ordered, what the advantage of using a MonetDB cluster? besides the replication in case of failure. Att, -- 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. http://www.avast.com

5 5

User for multiple schemas
by Brian Hood 14 Jul '15

14 Jul '15

Hi All, There is something I have pondered on is there a way to have a username that can be authorized for multiple schemas under your dbfarm. If not what is the reason ? I haven't seen a way to do this so far. Regards, Brian Hood

3 2

Reproducing EmbeddedR results from MonetDB.org site
by George, Glover E ERDC-RDE-ITL-MS 10 Jul '15

10 Jul '15

Hi all, I’ve recently been profiling several techniques for a workflow that we’ve been trying to improve here at USACE. Originally we used python scripts with sqlite, but we ran into scalability problems on large data sets. This led us to MonetDB, with the promise of columnar-based analysis and the hope of both parallel query’s “under-the-hood” and possibly a distributed workflow across an HPC system. Looking at my profiling results, this has led me to a number of questions that hopefully you all can help us with. I have a single table from the TPC-H benchmark – lineitem – populated with 360million entries: "l_orderkey" INTEGER NOT NULL, "l_partkey" INTEGER NOT NULL, "l_suppkey" INTEGER NOT NULL, "l_linenumber" INTEGER NOT NULL, "l_quantity" DECIMAL(15,2) NOT NULL, "l_extendedprice" DECIMAL(15,2) NOT NULL, "l_discount" DECIMAL(15,2) NOT NULL, "l_tax" DECIMAL(15,2) NOT NULL, "l_returnflag" CHAR(1) NOT NULL, "l_linestatus" CHAR(1) NOT NULL, "l_shipdate" DATE NOT NULL, "l_commitdate" DATE NOT NULL, "l_receiptdate" DATE NOT NULL, "l_shipinstruct" CHAR(25) NOT NULL, "l_shipmode" CHAR(10) NOT NULL, "l_comment" VARCHAR(44) NOT NULL, System Setup: Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz - 16 cores (HT off) / 256G RAM MonetDB version 11.19.15 R version 3.2.0 1. I have followed the instructions here: https://www.monetdb.org/content/embedded-r-monetdb and tried to reproduce these results. I only attempt to reproduce the results from R (reading the data from CSV since – as noted in a previous email to this list – R fails to read in the 360 million rows using MonetDB.R but works fine reading the same amount from CSV), MonetDB, as well as MonetDB with Embedded R. - I compile both R and MonetDB from source. When building R, I include the option to build the R shared library (libR.so) and when compiling MonetDB I include the option for embedded R. - When creating the MonetDB database, I set the option for embedr=true. - The R function from the above URL is used, as well as the same SQL query – and it works…. However, the performance is much worse than using R alone. I know I must be overlooking something. Please see the image at https://goo.gl/wUvB2J (png on Google Drive). The X-axis is the number of rows, and the Y axis is the time in seconds. As you can see, embedded R is unexpectedly much worse than the other two. 2. While running the quantile function, only one core is active – whether embeddedR or just MonetDB’s. 3. When running the following query (after altering the table to include a new column z, of course): sql>update lineitem set z=l_extendedprice / l_quantity; 360011594 affected rows (3m 49s) … Multiple cores are active for the first 10 seconds, then it resorts to single core. A. What am I not understanding about MonetDB’s ability to use multiple cores? The only time I really see it use multiple cores seems to be when doing “copy into”. B. Can someone provide assistance in trying to replicate the Embedded R results? Should it be running in parallel? Or might something in my setup be configured incorrectly. Cheers!

3 3

(no subject)
by musa 10 Jul '15

10 Jul '15

Can someone please provide a minimal example (how to start the server) for running the embedded R feature in windows? Regards, mpa

3 2