January 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

Disk I/O
by Tim Burress 02 Feb '15

02 Feb '15

Hello, I have a large database that is commonly used for relatively simple SELECT queries. Some of these can take quite a bit of time (hours... overnight) so I've been looking into it a bit. What seems clear is that mserver5 (Oct2014-SP1) is disk-bound, but one curious thing is that most of the time it is write-bound. Despite doing only SELECT queries (no updates or inserts), the amount of data being written is nearly two times as much as data read. Why is that? Is the server restructuring the database on the fly in order to get better performance in later queries? 3X the disk I/O seems excessive so I wonder if there is some way to tune this, or investigate further to see what is happening? Thanks! Tim

6 14

Upserts in MonetDB
by shamsul hassan 29 Jan '15

29 Jan '15

Hi All, I have been looking into UPSERTING records in MonetDB but didn't find anything. Only few years before somebody had asked the same question - https://www.monetdb.org/pipermail/users-list/2011-May/004916.html but no solution for that. Since its been few years from then , so I was wondering if MonetDB does provide the ability to do UPSERTS. Any pointers here will be really helpful. Thanks

2 1

Announcement: New Oct2014-SP2 Bugfix release of MonetDB suite
by Sjoerd Mullender 29 Jan '15

29 Jan '15

The MonetDB team at CWI/MonetDB BV is pleased to announce the Oct2014-SP2 bugfix 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/>. Oct 2014-SP2 bugfix release Client Package * Changes to the Perl interface, thanks to Stefan O'Rear: 1. removes "use sigtrap", because this has global effects and should not be used by modules, only by the application. 2. allows Perl 5.8.1+ Unicode strings to be passed to quote() and included in statements (UTF-8 encoded, as expected by Monet's str module) 3. quote and unquote now use the same quoting rules as the MonetDB server, allowing for all characters except NUL to be round-tripped 4. several character loops have been reimplemented in regex for much greater performance 5. micro-optimizations to the result fetch loop 6. block boundaries are preserved in piggyback data so that Xclose is not appended or prepended to a SQL command 7. diagnostic messages #foo before a result header are ignored, this is necessary to use recycler_pipe 8. fail quickly and loudly if we receive a continuation prompt (or any other response that starts with a non-ASCII character) 9. header lines must start with %, not merely contain %, fixing a bug when querying a table where string values contain % 10. after closing a large resultset, account for the fact that a reply will come and do not lose sync 11. allow a MAPI_TRACE environment variable to dump wire protocol frames to standard output 12. fixes maximum MAPI block size to match the server limit of 16k. previously would crash on blocks larger than 16k SQL * Fixed a typo in a column name of the sys.tablestoragemodel view (auxillary changed to auxiliary). Bug Fixes * 3467: Field aliases with '#' character excise field names in result set. * 3605: relational query without result * 3619: Missing dll on MonetDB Start * 3622: Type resolution error * 3624: insert of incomplete or invalid ip address values in inet column is silently accepted but the values are not stored (they become/show nil) * 3626: casting a type without alias results in program contains errors * 3628: mclient and ODBC driver report 'type mismatch' when stddev_pop used in a select which returns 0 rows * 3629: IF THEN ELSEIF always evaluates the first test as true * 3630: segv on rel_order_by_column_exp * 3632: running make clean twice gives an error in clients/ruby/adapter * 3633: Wrong result for HAVING with floating-point constant * 3640: Missing implementation of scalar function: sql_sub(<date>, <month interval>) * 3641: SQL lexer fails to detect string end if it the last character is U+FEFF ZERO WIDTH NO-BREAK SPACE * 3642: Combined WHERE conditions less-than plus equals-to produce incorrect results * 3643: Missing implementations of scalar function: sql_sub(<timetz>, arg2) * 3644: COPY INTO fails to import "inet" data type when value has prefix length in CIDR notation * 3646: ORDER BY clause does not produce proper results on 'inet' datatype * 3649: recycler crashes with concurrent transactions

2 1

Multiple insert into error
by Art Apl 27 Jan '15

27 Jan '15

Hi! I am trying to convert Lucene index into MonetDB with my app ( https://github.com/hjortron/LuceneToMonetDBConverter) App iterates through all Lucene docs and creates "insert into" query for each. First time problem appears on 80k row(and then dramatically falls down to 250 row), app throws error: INSERT INTO sys."EventTracking"(datetime,Hash,UserIP,EventType,SearchResultState,ViewType,PageNumber,ResultsCount,ElapsedTime) VALUES('2014-12-10 13:22:41','hod','127.0.0.1','Search','>No',0,0,2368195,85) Unhandled Exception: System.Data.Odbc.OdbcException: ERROR [HY000] [MonetDB][ODBC Driver 11.19.7]General error In merovingian.log I have only: "2015-01-26 00:43:03 ERR discovery[846]: cannot retrieve name info: Temporary failure in name resolution", that repeats each 30 minutes. On another instance of MonetDB my app works fine. Please help.

2 2

Database sharding across cluster in MonetDB
by Alastair McKinley 27 Jan '15

27 Jan '15

Hi all, I am wondering if there are any plans to develop horizontal sharding support for MonetDB? There aren't really other open source databases out there that support horizontal sharding with anywhere close to the performance of MonetDB. I realise there are a lot of challenges and scalability issues with a lot of typical DB operators, but for certain use cases that I have seen it could work really well, likely significantly faster than HBase/SparkSQL and it's rivals. Does anyone else think this would be a desirable feature? Best regards, Alastair

1 0

Best background refresh strategy
by Gustavo Brian 27 Jan '15

27 Jan '15

Hi, No changes done to the basic setup. I'm running OLAP queries and not all 54 columns are used in any query, it depends on the query which columns are used. The query is kind of SELECT SUM(),AVG(), SUM() + WHERE + GROUP BY The WHERE columns have a great compression so it's faster to find by them. My last test runs in 340 ms and aggregates between 900 and 2000 rows per result. Care: "select * from table where key = 123456" (not an expert but this is pure OLTP) Same for me, "select * from bigcalendar limit 2" -> Sometimes I have to kill it, :) but it's something that I don't need at all. I'm using MonetDB as a kind of cache of my OLTP system. IMO MonetDB is perfect for OLAP (not only analytical, operational as well! Now I'm working on the refresh approach) if you are looking for a fast search engine by key, maybe a pure key/value-store is more appropriate. Hope this helps. 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: martes, 27 de enero de 2015 12:00 To: users-list(a)monetdb.org Subject: users-list Digest, Vol 29, Issue 20 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. Re: Best background refresh strategy (shamsul hassan) 2. Join index structure (Joseph D'silva) ---------------------------------------------------------------------- Message: 1 Date: Mon, 26 Jan 2015 11:44:49 +0000 From: shamsul hassan <shamsulbuddy(a)gmail.com> To: Communication channel for MonetDB users <users-list(a)monetdb.org> Subject: Re: Best background refresh strategy Message-ID: <CAONo-dtZpv4LfhKrM+cCh7tZcsDM4daTU80rLigcQR-ruYEbag(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" *338 million rows / 54 columns table and ran queries in ms* -- WOW .. Do you mind sharing your server configuartion and the setting for mserver5. Also what kind of queries are you firing .. ?? I find it bit slow on line level queries , something like select * from table where key = 123456 Thanks On Sun, Jan 25, 2015 at 6:56 AM, Martin Kersten <martin(a)monetdb.org> wrote: > On 25/01/15 06:48, Gustavo Brian wrote: > >> Hi, >> > Hi, > > thanks for the interest and appraisal. > >> >> I'm trying monetdb as a bigtable for calendar based queries. >> I've created a 338 million rows / 54 columns table and ran queries in ms. >> That's perfect! >> I wonder to see if monetdb is suitable for a search service with high >> traffic (several hundred request per second) and which will the best >> data update strategy because during the "updates/insert/copy into" >> actions everything gets blocked. >> > Queries should not be a problem, but for updates you should read and > understand > https://www.monetdb.org/blog/monetdb-sql-transaction-management-scheme > https://www.monetdb.org/Documentation/Manuals/SQLreference/Transaction > s > > I would like to know how cluster mode will help as well. >> > Depends on the complexity of the query and your machine specs. > regards, Martin > > >> Thanks, >> Gustavo Brian >> _______________________________________________ >> users-list mailing list >> users-list(a)monetdb.org >> https://www.monetdb.org/mailman/listinfo/users-list >> >> > _______________________________________________ > users-list mailing list > users-list(a)monetdb.org > https://www.monetdb.org/mailman/listinfo/users-list >

1 0