- users-list - monetdb.org

couple of unanswered qs
by Anthony Damico 18 Sep '15

18 Sep '15

https://stackoverflow.com/questions/tagged/monetdb

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Why doesn't MonetDB exploit SIMD feature?
by Xu,Wenjian 18 Sep '15

18 Sep '15

Hi, We know that MonetDB excels in application where the database hot-set can be largely held in main-memory, since the physical operators (e.g., hashjoin, sort) are highly optimized for main-memory. But it is strange to me that these operators do not utilize SIMD which a performance-critical feature of modern CPUs. For example, MonetDB use *timsort* as its underlying stable sort algorithm (do_ssort() in gdk/gdk_ssort_impl.h), but I cannot find any SIMD instructions there. Why doesn't MonetDB exploit SIMD feature? or did I miss something? In paper 'Vectorwise: Beyond Column Stores', the authors claim that X100/Vectorwise use SIMD instructions. So my follow-up question is that whether any of X100/Vectorwise's technologies/features has been integrated into MonetDB's code base. Thank you. Best regards, Xu, Wenjian

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Encrypted Client Sessions
by James Candalino 17 Sep '15

17 Sep '15

Hi all, Is it possible to establish encrypted client sessions? If so, how? I didn't see anything in the documentation. With postgres connecting using jdbc is just jdbc:postgresql://dbhost/dbname?ssl=true. Any insight would be greatly appreciated. --James -- *NOTICE TO RECIPIENTS*: This communication is confidential and intended for the use of the addressee only. If you are not an intended recipient of this communication, please delete it immediately and notify the sender by return email. Unauthorized reading, dissemination, distribution or copying of this communication is prohibited. This communication does not constitute an offer to sell or a solicitation of an indication of interest to purchase any loan, security or any other financial product or instrument, nor is it an offer to sell or a solicitation of an indication of interest to purchase any products or services to any persons who are prohibited from receiving such information under applicable law. The contents of this communication may not be accurate or complete and are subject to change without notice. As such, Orchard App, Inc. (including its subsidiaries and affiliates, "Orchard") makes no representation regarding the accuracy or completeness of the information contained herein. The intended recipient is advised to consult its own professional advisors, including those specializing in legal, tax and accounting matters. Orchard does not provide legal, tax or accounting advice.

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Accessing admin GUI
by Peter Smith 17 Sep '15

17 Sep '15

Hi, https://www.monetdb.org/XQuery/Tutorials/adminGUI It looks as if the admin GUI should automatically start up on 50001/TCP when I start MonetDB, but this doesn't seem to be the case: I have monetdb listening on 50000, but nothing listening on 50001. I'm running MonetDB 11.19 on Ubuntu. I'm using an init.d script to start MonetDB, and here's the running process: /usr/bin/mserver5 --dbpath=/home/administrator/monetdb/xxx/xxx --set merovingian_uri mapi:monetdb://127.0.0.1:50000/xxx --set mapi_open false --set mapi_port 0 --set mapi_usock /home/administrator/monetdb/xxx/xxx/.mapi.sock --set monet_vault_key /home/administrator/monetdb/xxx/xxx/.vaultkey --set gdk_nr_threads 16 --set max_clients 64 --set sql_optimizer default_pipe --set monet_daemon yes Do I need to pass extra start-up options to enable the GUI? (I don't see anything in the mserver5 man page) Thanks, Peter Smith

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What is the difference ?
by Brian Hood 16 Sep '15

16 Sep '15

Hi All, So the new CREATE REPLICA TABLE definition / CREATE TABLE definition i'm not sure what the difference would be ? CREATE REPLICA TABLE test2 AS (SELECT * FROM test) WITH DATA; CREATE TABLE test2 AS (select * from test) WITH DATA; Regards, Brian Hood

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Inserting in 'raw' mode??
by Vijay Krishna 15 Sep '15

15 Sep '15

Hi, I was analysing the Insert performance of MonetDB... I am trying to optimize a process where in a single tuple has to be inserted into a table of 1200 columns, which takes about 7.5 seconds presently... The query has values for only 5 columns out of 1200, yet the speed is still the same.. Is it possible to reduce this time even?? While digging on this, I came across this thread.. https://www.monetdb.org/pipermail/users-list/2005-August/000139.html *What is the insert speed relatively to other DBs? > * > Using SQL, with the current version we won't compete very well. We get > much more acceptable speeds in 'raw' mode, where lots of the parsing > overhead is removed. > > Can anyone please help me understand what is the 'raw' mode that is explained in this thread?? I am using Oct-2014 version on a CentOS machine with 128 GB RAM... Thanks & Regards, Vijayakrishna.P. Mobile : (+91) 9500402305.

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DbVisualizer support for MonetDB
by Robert Koch 14 Sep '15

14 Sep '15

Hi Folks, DbVisualizer is my preferred GUI to MonetDB. DbVis offers capability to write own database profiles for specific DB's. Today I committed a MonetDB database profile for DbVisualizer. https://github.com/dbvisualizer/dbvis-database-profiles/tree/master/monetdb Anyone familiar to DbVis can import and/or improve this profile. There's a free DbVis version, but the Pro offers much more features, which make life easier. BTW, I'm not working for them. :-) Please feel free to write me your desired features by mail or directly into the MD-file inside the monetdb-directory. If possible, I will implement it inte the profile. Best regards Mario

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`/usr/bin/mserver5': double free or corruption
by Brian Hood 10 Sep '15

10 Sep '15

Hi Guys, I created a brand new directory for my dbfarm yesterday and as you can see everything was fine for 24 hours then my merovingian.log shows an error. My Compile options are: ./configure --libdir=/usr/lib64 --prefix=/usr --sysconfdir=/etc --localstatedir=/var --disable-assert \ --disable-testing --enable-optimize --enable-rintegration --enable-jsonstore http://pastebin.com/qAebcMhp I'm currently only inserting to one table. DROP TABLE "threatmonitor".http_traffic_json; CREATE TABLE "threatmonitor".http_traffic_json ( id INT GENERATED ALWAYS AS IDENTITY ( START WITH 0 INCREMENT BY 1 NO MINVALUE NO MAXVALUE CACHE 2 CYCLE ) primary key, guid char(36), recv_date date, recv_time time, json_data JSON ); Typical insert INSERT INTO http_traffic_json (recv_time,recv_date,guid,json_data) VALUES (NOW(), NOW(), '1f248d6e-ed15-2a3e-a08f-96536ed925d0', '{"http":{"host":"ad.sxp .smartclip.net","connection":"keep-alive","cachecontrol":"max-age=0","accept":"image/webp,*/*;q=0.8","useragent":"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/4 2.0.2311.90 Safari/537.36","referer":" http://cdn.turn.com/server/ddc.htm?uid=8915259122209287941&rnd=246995741890…","acceptencoding":"gzip, defla te, sdch","acceptlanguage":"en-GB,en-US;q=0.8,en;q=0.6","cookie":"ommited"}}'); I will look more at this tomorrow and try and reproduce. Regards, Brian Hood

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Issue upgrading from 11.17.9 to 11.21.5
by Brian Hood 09 Sep '15

09 Sep '15

Hi All, I am unsure what to do in this scenario. Can anyone help ? http://pastebin.com/LwLCLeAB 1. 2015-09-08 13:40:07 MSG threatmonitor[31747]: # Listening for UNIX domain connection requests on mapi:monetdb:///data2/threatmonitor/threatmonitor/.mapi.sock 2. 2015-09-08 13:40:07 MSG threatmonitor[31747]: # Start processing logs sql/sql_logs version 52200 3. 2015-09-08 13:40:07 ERR threatmonitor[31747]: !FATAL: Incompatible database version 052001, this server supports version 052200. 4. 2015-09-08 13:40:07 ERR threatmonitor[31747]: Maybe you need to upgrade to an intermediate release first. 5. 2015-09-08 13:40:07 ERR threatmonitor[31747]: 6. 2015-09-08 13:40:07 MSG merovingian[31739]: database 'threatmonitor' (31747) has exited with exit status 1 7. 2015-09-08 13:40:07 ERR control[31739]: (local): failed to fork mserver: database 'threatmonitor' appears to shut itself down after starting, check monetdbd's logfile for possible hints Regards, Brian Hood

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Announcement: New Jul2015 Feature release of MonetDB suite
by Sjoerd Mullender 09 Sep '15

09 Sep '15

The MonetDB team at CWI/MonetDB BV is pleased to announce the Jul2015 feature release of the MonetDB suite of programs. More information about MonetDB can be found on our website at <http://www.monetdb.org/>. For details on this release, please see the release notes at <http://www.monetdb.org/Downloads/ReleaseNotes>. As usual, the download location is <http://dev.monetdb.org/downloads/>. Jul 2015 feature release MonetDB5 Server * Implemented batcalc.min and batcalc.max. Made calc.min and calc.max generic so that no other implementations are needed. * Removed function batcalc.ifthen. Build Environment * Upgraded the license to the Mozilla Public License Version 2.0. Client Package * Added a new output format to mclient: --format=expanded (or -fx). In this format, column values are shown in full and below each other. MonetDB Common * BUNtvar and BUNhvar macros no longer work for TYPE_void columns. * Changed interfaces of a lot of GDK-level functions. When they modify a BAT, don't return the same BAT or NULL, but instead return GDK_SUCCEED or GDK_FAIL. * Changed a bunch of hash-related functions to work on the tail column. The functions that have been changed to work on the tail column are: BAThash, BATprepareHash, HASHgonebad, HASHins, and HASHremove. Java Module * Improved JDBC driver to not throw NullPointerException anymore when calling isNullable() or getPrecision() or getScale() or getColumnDisplaySize() or getSchemaName() or getTableName() or getColumnClassName() on a ResultSetMetaData object. * We now compile the Java classes using the latest Java 1.8 version, and we tell it to compile for Java 1.7. SQL * Differences between time, timestamp, and date values now return properly typed interval types (second or month intervals) instead of integers. * Added support for 128-bit integers (called HUGEINT) on platforms that support this. * Removed support for the mseed library. * Removed support for RDF. * Removed DataCell. It was experimental code that was never enabled. Bug Fixes * 2618: Implement master slave scheme * 3361: constants as MAL function parameters prevent intermediate reuse * 3364: Cannot set role back to a user's default role * 3365: Unable to grant object privileges while having a non-default current_role * 3440: Sequence type errors * 3449: mserver crash on start - Freebsd 10 amd64 * 3476: Cannot revoke object access * 3496: autocompletion table names does not work correctly * 3556: when 2 multiplexed functions in MAL plan, only one is mapped correctly to bat<mod>.function primitive * 3564: Request: add support for postgresql specific scalar function: split_part(string text, delimiter text, field int) * 3625: SIGSEGV because mat array can overrun in opt_mergetable.c * 3627: SQRT in CASE does not work as of Oct2014 * 3654: configure --enable-fits requires extra commands after creating a database instance * 3673: mclient 'expanded' row formatter * 3674: Obfuscate event tracing * 3679: No error is given when incorrect timezone value is specified for a timetz column * 3686: Wrong associativity of multiply/divide * 3702: Filter function not found if created in a user schema * 3708: wrong scoping for cross-schema view references * 3716: alter table my_merge_table drop table t1; crashes mserver5 with Segmentation fault * 3724: Wrong size calculation in BATsubjoin * 3730: SAMPLE function not sampling randomly * 3732: memory leak (of InstrRecord) in opt_mergetable * 3733: "(TRUE OR <Exp>) AND <Exp>" is evaluated incorrectly * 3735: python connection with unix_socket * 3736: crash if mclient disconnects abruptly during a query * 3738: Database inconsistency when using savepoint * 3739: CASE statements do not handle NULLs in the IN () operator properly * 3740: select epoch(now()); types timestamptz(7,0) and bigint(64,0) are not equal * 3742: Division By Zero * 3744: cast to int gives different results for decimal than double * 3747: joins fail in the presence of nulls * 3748: Missing META-INF/services/java.sql.Driver in JDBC package * 3753: Hang on json field parsing * 3754: select from a REMOTE TABLE referring local table crashes mserver5 * 3756: column type conversion sticks to subsequent queries * 3758: "COPY INTO ..." doesn't work, if executing from 2 processes concurrently. * 3759: select data from "sys"."rejects" returns unexpected error and when next select data from "sys"."sessions" causes an assertion failure in mal_interpreter.c:646. * 3760: SQL parser has problem with (position of) a scalar subquery in a SELECT-list * 3761: SQL executor has problem with (position of) a subquery in a SELECT-list. Inconsistent behavior. * 3763: JDBC PreparedStatement for a table with 14 Foreign Keys crashing the Database * 3764: DROPping multiple users causes a crash * 3765: Re-granting a revoked privilege does not work * 3766: VIEW not visible if created under a different schema * 3767: CREATE TEMP TABLE using "LIKE" incorrectly handled * 3769: SIGSEGV when combining a cast/column alias with a UNION ALL view * 3770: combined conditions on declared table in User Defined Function definition crashes monetdb * 3771: Owner of the schema loses rights if assumes the monetdb role. * 3772: Any user can grant a role. * 3773: quantile(col, 0) and quantile(col, 1) fail * 3774: mclient is unaware of merge tables and remote tables * 3775: COPY INTO: Backslash preceding field separator kills import * 3778: Crash on remote table schema mismatch * 3779: server crashes on MAX() on SELECT DISTINCT something combo * 3783: Behavioural change in Jul2015 for 'timestamp minus timestamp' * 3784: Assertion failed: (bn->batCapacity >= cnt), function BAT_scanselect, file gdk_select.c, line 1008. * 3785: sum(interval) causes overflow in conversion to bte * 3786: ResultSet.close() never sends Xclose to free resources * 3787: "b and g must be aligned" from complex group/union query * 3791: HEAPextend: failed to extend to 2420077101056

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Jul2015: access denied to sys.tables from custom user/schema
by Roberto Cornacchia 02 Sep '15

02 Sep '15

Hi there, Is it a Jul2015 feature that access to sys.tables is denied to custom a user/schema? However, sys._tables is accessible. That sounds strange. Roberto

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I love Jul2015!
by Roberto Cornacchia 01 Sep '15

01 Sep '15

Not about issues this time. I just wanted to thank the team for this new upcoming release, I'm using it for a while already and it seems to be brilliant. I particularly like that hash tables are kept around, making a hot DB solve in *microseconds* joins that would take almost half a *second* otherwise. Ka-Boom!

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Release Jul2015
by Luciano Sasso 31 Aug '15

31 Aug '15

Jul2015 is stable version ? This master/slave(master pull data for salave automatic) features this release Jul2015? -- 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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Information for Datastorage, Indizes and Query optimization
by Dennis Wiest 31 Aug '15

31 Aug '15

Hello there, there is detailed information about MonetDB with respect to the data storage, indexing and query optimization. I think, unfortunately, on the website is not very much. Special for the Internal index and query optimization. Can you help me there? I need that for my work. greetings Wiest Dennis ________________________________ Avitech GmbH Principal Office: Bahnhofplatz 1 | 88045 Friedrichshafen | Germany Court Registration: Amtsgericht Ulm | HRB 728293 Gesch?ftsf?hrer/Managing Director: Antonio Maria Gonzalez Gorostiza VAT No.: DE223719716 http://avitech.aero

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dplyr & monetdb - appropriate syntax for querying schema.table?
by Enzo 31 Aug '15

31 Aug '15

I’ve just posted the following on stackoverflow. Any help is welcome! In monetdb I have set up a schema main and my tables are created into this schema. For example, the department table is main.department. With dplyr I try to query the table: mdb <- src_monetdb(dbname="model", user="monetdb", password="monetdb") tbl(mdb, "department") But I get Error in .local(conn, statement, ...) : Unable to execute statement 'PREPARE SELECT * FROM "department"'. Server says 'SELECT: no such table 'department'' [#42S02]. I tried to use "main.department" and other similar combinations with no luck. What is the appropriate syntax? Enzo enzo(a)smartinsightsfromdata.com

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password issue with Jul2015 Feature release of MonetDB suite
by Enzo 29 Aug '15

29 Aug '15

I do not seem to be able to log in R: the following was working before, but now it doesn’t. aconn <- dbConnect(MonetDB.R(), "monetdb://localhost:50000/ClevelandBaseModel", user= "monetdb", password="monetdb”) Error in .mapiAuthenticate(socket, dbname, user, password, language = language) : Authentication error: !InvalidCredentialsException:checkCredentials:invalid credentials for user ‘monetdb’ Has the password been changed?? Enzo enzo(a)smartinsightsfromdata.com

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issue granting administrator rights
by Enzo 28 Aug '15

28 Aug '15

I have successfully managed to configure multi-user access to my user defined schema. All the users are granted monetdb “rights with: GRANT monetdb TO user1 Once logging the new user has ability to SELECT / DROP / INSERT etc. in the user schema. Sadly at the time of executing the MonetDB.R command: tStatus <- dbWriteTable(conn, tPFile, dataDt,overwrite=TRUE, csvdump=TRUE) I’ve got: Unable to execute statement 'COPY OFFSET 2 INTO demand FROM '/Users/xxx/demand.csv' USIN...'. Server says '!COPY INTO: insufficient privileges: COPY INTO from file(s) requires database administrator rights, use 'COPY INTO "demand" FROM STDIN' instead' So clearly GRANT monetdb TO user1 is not enough to empower user1. I tried: GRANT monetdb to “user1" WITH ADMIN OPTION; But at this point after: SET SCHEMA cleveland; SET ROLE monetdb; I get error "Role (monetdb) missing” It does not seem correct to me: surely it should be possible to grant rights to a user at the same level of “monetdb”, including administrator rights? Enzo enzo(a)smartinsightsfromdata.com

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Re: any idea what's going on here? it was created under the previous version but now isn't loading after upgrade
by Niels Nes 28 Aug '15

28 Aug '15

On Fri, Aug 28, 2015 at 06:29:38AM -0400, Anthony Damico wrote: > hi, thanks, here's the file from > > R:\American Community Survey\MonetDB\acs\bat\BACKUP\BBP.dir So the db upgrade did create the sql_dsnapshots bat, but its not part of the sql catalog. Fixed a bug in the code for this now. Niels > > On Fri, Aug 28, 2015 at 5:56 AM, Niels Nes <Niels.Nes(a)cwi.nl> wrote: > > On Thu, Aug 27, 2015 at 02:09:22PM -0400, Anthony Damico wrote: > > # MonetDB 5 server v11.21.3 "Jul2015" > > # Serving database 'acs', using 4 threads > > # Compiled for x86_64-pc-winnt/64bit with 64bit OIDs dynamically > linked > > # Found 64.000 GiB available main-memory. > > # Copyright (c) 1993-July 2008 CWI. > > # Copyright (c) August 2008-2015 MonetDB B.V., all rights > reserved > > # Visit http://www.monetdb.org/ for further information > > # Listening for connection requests on mapi:monetdb:// > 127.0.0.1:50001/ > > # Start processing logs sql/sql_logs version 52200 > > !FATAL: Logger_new: BBPrename to sql_dsnapshots failed > > Press any key to continue . . . > > > _______________________________________________ > > users-list mailing list > > users-list(a)monetdb.org > > https://www.monetdb.org/mailman/listinfo/users-list > > Anthony > > As the server doesn't successfully start we need to see why the > rename > fails. Could you check the BBP.dir file (usualy in the bat > directory of > your dbpath, sometimes in the BACKUP directory there), and see > if a bat with this name exists (sql_dsnapshots). > > Niels > > > -- > Niels Nes, Manager ITF, Centrum Wiskunde & Informatica (CWI) > Science Park 123, 1098 XG Amsterdam, The Netherlands > room L3.14, phone ++31 20 592-4098 sip:4098@sip.cwi.nl > url: https://www.cwi.nl/people/niels e-mail: Niels.Nes(a)cwi.nl > _______________________________________________ > users-list mailing list > users-list(a)monetdb.org > https://www.monetdb.org/mailman/listinfo/users-list > > -- Niels Nes, Manager ITF, Centrum Wiskunde & Informatica (CWI) Science Park 123, 1098 XG Amsterdam, The Netherlands room L3.14, phone ++31 20 592-4098 sip:4098@sip.cwi.nl url: https://www.cwi.nl/people/niels e-mail: Niels.Nes(a)cwi.nl

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any idea what's going on here? it was created under the previous version but now isn't loading after upgrade
by Anthony Damico 28 Aug '15

28 Aug '15

# MonetDB 5 server v11.21.3 "Jul2015" # Serving database 'acs', using 4 threads # Compiled for x86_64-pc-winnt/64bit with 64bit OIDs dynamically linked # Found 64.000 GiB available main-memory. # Copyright (c) 1993-July 2008 CWI. # Copyright (c) August 2008-2015 MonetDB B.V., all rights reserved # Visit http://www.monetdb.org/ for further information # Listening for connection requests on mapi:monetdb://127.0.0.1:50001/ # Start processing logs sql/sql_logs version 52200 !FATAL: Logger_new: BBPrename to sql_dsnapshots failed Press any key to continue . . .

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Multiple MonetDB nodes behind HAProxy loadbalancer
by Dennis Pallett 20 Aug '15

20 Aug '15

Hi all, We're thinking about running multiple MonetDB servers with the same databases behind a single HAProxy loadbalancer (see attached diagram). Would this be a good idea? bad idea? Any experiences with this kind of setup? We are thinking about this route primarily so that we can bring a new dataset online during business hours without disrupting end-users who are running queries from our application. An additional benefit would be the ability to handle more load and enable horizontal scalability. Any insights would be much appreciated! Best regards, Dennis

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Jul2015 Release Candidate
by Sjoerd Mullender 19 Aug '15

19 Aug '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 I have created a release candidate for the Jul2015 release. The candidate is available at http://dev.monetdb.org/downloads/testing/. If all goes well, this candidate will morph into a release sometime soon(ish). In the mean time, you can use this release candidate and test to see whether it works. And if it doesn't work, I would really like to hear about it. - -- Sjoerd Mullender -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJVyKZgAAoJEISMxT6LrWYgE28H/2rudFXhcIfNgnX4yYJlpRT5 eI2Dzp9kShEmRibvNkWvCEF1j/qyWgQhx/jlHvucuEF/0k+U+7NYuK0vhzA0llyJ hspMkQ73UDXeVO0/SivtNYb40UpMyUQoXC7nSaSneglVDe4JcX4S3Y5GvHPByiqz 3UNMGDARfWlqPcbTtW57XfLejK/sd8nNZ3mGQuerVqEvMcKZaZIBSXjg/16WQVsN DMbPacPpu3yFeWQQtP2er6SL3UdfwgOP5+VNifKyjW9i6ZtB2lHWLEBWQY8G/5Tb 5lwgHvD99SJeLRMzcW5TFWhwv0ROx8chKP3btxMofZxjHhqseswGRLNDQa4XCU0= =ktpg -----END PGP SIGNATURE-----

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RE: Concurrent queries problem (Gustavo Brian)
by Gustavo Brian 18 Aug '15

18 Aug '15

Hi, After checking CPU (48 cores) none of them get over 15%, there's free memory (119Gb) and 0% reads but high WRITE activity, any idea why? Thanks, Gustavo Brian Developer -----Original Message----- From: users-list [mailto:users-list-bounces+gustavo.brian=sunhotels.net@monetdb.org] On Behalf Of users-list-request(a)monetdb.org Sent: lunes, 17 de agosto de 2015 12:00 To: users-list(a)monetdb.org Subject: users-list Digest, Vol 36, Issue 19 Send users-list mailing list submissions to users-list(a)monetdb.org To subscribe or unsubscribe via the World Wide Web, visit https://www.monetdb.org/mailman/listinfo/users-list or, via email, send a message with subject or body 'help' to users-list-request(a)monetdb.org You can reach the person managing the list at users-list-owner(a)monetdb.org When replying, please edit your Subject line so it is more specific than "Re: Contents of users-list digest..." Today's Topics: 1. Concurrent queries problem (Gustavo Brian) 2. Re: Concurrent queries problem (Martin Kersten) 3. Inserting in 'raw' mode?? (Vijay Krishna) ---------------------------------------------------------------------- Message: 1 Date: Sun, 16 Aug 2015 17:07:41 +0000 From: Gustavo Brian <Gustavo.Brian(a)sunhotels.net> To: "users-list(a)monetdb.org" <users-list(a)monetdb.org> Subject: Concurrent queries problem Message-ID: <4A8379DA0ABDFC42B172EDB698BD76E8D46EF829@mailbox02> Content-Type: text/plain; charset="iso-8859-1" Hi, I'm using one big table a my main storage for hotel prices and I'm running queries to get the best prices for specific dates and a couple of filters. On one test I have a query scanning 30 millions rows in ~400ms but when I try to run several queries at a time monetdb hangs. I've tried creating a funnel over the database but same result. What's the best approach if I need to run 150 queries per second ? Thanks in advance, Gustavo Brian Developer SunHotels E-mail Skype Tel Fax Web Operational Office gustavo.brian(a)sunhotels.net<mailto:gustavo.brian@sunhotels.net> Gustavo.brian.sunhotels +34 871 955 649 +34 971 281 460 www.sunhotels.org SunHotels Calle Cal?at 6 Pol?gono Son Valent? 07011 Palma de Mallorca Spain >> Winner of Grand Travel Award - Best Provider in Scandinavia << Confidential and proprietary information notice: This message (including any attachments) contains confidential information intended for a specific individual and purpose, and is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited. Please preserve message history when replying to this e-mail

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Re: MonetDB performance disappointing
by Martin Schwitalla 17 Aug '15

17 Aug '15

Hi, sorry that it took so long but I could test the patch and it didn`t seem to change anything. The trace looks the same and the performance didn`t improve. Regards, Martin

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Concurrent queries problem
by Gustavo Brian 16 Aug '15

16 Aug '15

Hi, I'm using one big table a my main storage for hotel prices and I'm running queries to get the best prices for specific dates and a couple of filters. On one test I have a query scanning 30 millions rows in ~400ms but when I try to run several queries at a time monetdb hangs. I've tried creating a funnel over the database but same result. What's the best approach if I need to run 150 queries per second ? Thanks in advance, Gustavo Brian Developer SunHotels E-mail Skype Tel Fax Web Operational Office gustavo.brian(a)sunhotels.net<mailto:gustavo.brian@sunhotels.net> Gustavo.brian.sunhotels +34 871 955 649 +34 971 281 460 www.sunhotels.org SunHotels Calle Calçat 6 Polígono Son Valentí 07011 Palma de Mallorca Spain >> Winner of Grand Travel Award - Best Provider in Scandinavia << Confidential and proprietary information notice: This message (including any attachments) contains confidential information intended for a specific individual and purpose, and is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited. Please preserve message history when replying to this e-mail

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Maximum number of tables
by Masood Mortazavi 15 Aug '15

15 Aug '15

Hi -- Is there a configured maximum number of tables supported by a MonetDB instance? Maximum number of columns in a table? What's the rough size of metadata per column at run-time? Thanks, - Masood

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