- users-list - monetdb.org

[MonetDB-users] MonetDB XQuery Bulk Load / Bulkload
by Alexander Koglin 07 Feb '10

07 Feb '10

I have currently installed a version of MonetDB XQuery for Linux and want to bulkload data like this: http://monetdb.cwi.nl/XQuery/Documentation/Bulk-Loading-a-Collection.html#B… For that purpose, I used the following command inside the Client: for $d in doc("/monetdbfiles.xml")//doc return pf:add-doc(fn:concat($d/@path,$d/@name), fn:string($d/@name), "abap10k", 0) <> It references the following, definitely existing XML file: <dir> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCDEF"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCIMP"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCMAC"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CI"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM001"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM002"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM003"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM004"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM005"> </dir> But unfortunately an error is thrown (I also tried it unter Windows and it was the same): MAPI = root@localhost:50000 QUERY = for $d in doc("/monetdbfiles.xml")//doc ERROR = !ERROR: err:FODC0002, Error retrieving resource (no such document "/monetdbfiles.xml"). What could be the reason for that?

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[MonetDB-users] authorize! what's wrong?
by korisk 07 Feb '10

07 Feb '10

Hi! I've installed monetdb from sources. ./MonetDB5-server-5.16.4.tar.bz2 ./MonetDB-client-1.34.4.tar.bz2 ./MonetDB-SQL-2.34.4.tar.bz2 merovingan started database test created but mclient asks for password! and i don't know which one. Manual says that monetdb uses system authorization, but mclient answers: korisk@pс64:~$ mclient -l sql -d test user(korisk): password: InvalidCredentialsException:checkCredentials:invalid credentials for user 'korisk' i use Ubuntu 9.10 x86_64 What's wrong? Thank you.

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[MonetDB-users] authorization! what's wrong?
by korisk 07 Feb '10

07 Feb '10

Hi! I've installed monetdb from sources. ./MonetDB5-server-5.16.4.tar.bz2 ./MonetDB-client-1.34.4.tar.bz2 ./MonetDB-SQL-2.34.4.tar.bz2 merovingan started database test created but mclient asks for password! and i don't know which one. Manual says that monetdb uses system authorization, but mclient answers: korisk@pс64:~$ mclient -l sql -d test user(korisk): password: InvalidCredentialsException:checkCredentials:invalid credentials for user 'korisk' i use Ubuntu 9.10 x86_64 What's wrong? Thank you.

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[MonetDB-users] connecting streams to Mapi.
by Guillaume Yziquel 05 Feb '10

05 Feb '10

Hi. I'm investigating how to connect custom streams to a Mapi structure. I've been reading, for instance the start_mal_server() function of monetdb5-server-5.16.2/src/tools/embeddedclient.c.in. I now sort of understand how the stream library works (though not fully), and I'm trying to understand how the streams are effectively used by the client of the Mapi struct. I've therefore looking at the start_mal_server() function, and here's a piece of code whose semantics I do not understand: > in = ((stream **) arg)[0]; > out = ((stream **) arg)[1]; > free(arg); > snprintf(buf, sizeof(buf), > "in := \"" PTRFMT "\":streams;\n" > "out := \"" PTRFMT "\":streams;\n" > "mapi.malclient(in, out);\n", PTRFMTCAST in, PTRFMTCAST out); > callString(mal_clients, buf, 0); I'm specifically interested in the 'in' stream since it is the one I would like to write to. Could someone enlighten me here? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] Feb2010 64 bit starts and immediately stops on Windows
by Alex Bo. 05 Feb '10

05 Feb '10

Hi dear MonetDB people, I built MonetDB 64 bit on Windows from the Feb2010 branch today. Everything ran fine, but when I start the server, after seeing the normal output, it immediately dissapears. Here's the output: # MonetDB server v5.18.0, based on kernel v1.36.0 # Serving database 'demo', using 1 thread # Compiled for i686-pc-win32/64bit with 32bit OIDs dynamically linked # Found 1.999 GiB available main-memory. # Copyright (c) 1993-July 2008 CWI. # Copyright (c) August 2008-2010 MonetDB B.V., all rights reserved # Visit http://monetdb.cwi.nl/ for further information #warning: please don't forget to set your vault key! #(see C:\MonetCVS_base_Feb10\MonetCVS64_cleanBuild\Install\etc\monetdb5.conf) # Listening for connection requests on mapi:monetdb://127.0.0.1:50000/ # MonetDB/SQL module v2.36.0 loaded Building MonetDB 32 bit works just fine. Thanks. -- View this message in context: http://old.nabble.com/Feb2010-64-bit-starts-and-immediately-stops-on-Window… Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] MCinitClient() and user oid.
by Guillaume Yziquel 05 Feb '10

05 Feb '10

Hi. I've been trying to get access to the Client structures on the server side. I've therefore been looking at MCinitClient(). What I do not understand is how do you know which oid for the user you should pick, in order to pass this oid as an argument to MCinitClient. > http://yziquel.homelinux.org/topos/api/ocaml-monetdb5/MonetDB5.MAL.Client.h… > > Client MCinitClient(oid user, bstream *fin, stream *fout) Moreover, it seems to me that in an embedded setting, it doesn't seem to be a smart idea to use MCinitClient. It would perhaps be better to grab the already existing Client structure for the admin. Probably with MCfindClient. > http://yziquel.homelinux.org/topos/api/ocaml-monetdb5/MonetDB5.MAL.Client.h… > > Client MCfindClient(oid user, str scen, bstream *fin, stream *fout) fin and fout seem optional arguments (meaning you can pass NULL for sensible defaults). But as before, the oid of the user, and the sceanrio string are arguments whose proposed values are unclear to me. How do you get the admin's Client struct? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] copy into with 'float' types crashes
by Alex Bo. 04 Feb '10

04 Feb '10

Hi, I am encountering something very strange. (Windows - NovSP1 from CVS) On some machines I encountered crashes in Monet when doing a copy into on tables with a float column. After trying to investigate, I narrowed it down to this: Run: 1. CREATE TABLE test (f1 int, f2 float); 2. COPY INTO test from 'filename.txt' using delimiters ',','\n','"' null as ''; the text file contains: 1,1 2,2 This sequence exactly caused a server crash (without any message) on some machines, while on others it didn't. The machines it happened on were: 1. 32 bit XP with 3 GB RAM. 2. 32 bit Vista with 4 GB RAM. In both cases, changing the column type from float to real worked. Could it be that float, being a 64 bit floating point, might cause crashes on 32 bit machines? Is there anything I can to help you get a clearer picture of this? Thanks. -- View this message in context: http://old.nabble.com/copy-into-with-%27float%27-types-crashes-tp27438598p2… Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] The maximum used memory option
by Stefan de Konink 04 Feb '10

04 Feb '10

It was discussed before that there should exist an option to limit the amount of 'detected' memory to a certain value. Is this option available, if so, what is its syntax? The other way around was to use ulimit on the process, does this mean MonetDB will get a sigkill if it grows out of boundaries or will it just use that value as upper memory limit? Stefan

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[MonetDB-users] Problem using win 32 odbc driver
by klaas＠maxml.nl 04 Feb '10

04 Feb '10

Good morning, I'm using MonetDB v5.16.2 on windows xp 32. Connecting to the database with Java clients works fine, odbc (version 10.1.12) is not. Table DDL: CREATE TABLE _r_language( id smallint NOT NULL AUTO_INCREMENT, abbrev varchar(3) NOT NULL, name varchar(50) NOT NULL, primary key (id) ); For example in php: <?php $conn = odbc_connect('DSN=MonetDB;HOST=localhost;PORT=50000', 'monetdb', 'monetdb') or die('unable to connect'); $result = odbc_exec($conn, 'select * from _r_language;'); odbc_result_all($result); ?> results in: ? ?? ??? 1 English EN 2 German DE 3 French FR 4 Dutch NL 5 Polish PL The fieldnames are not returned. Using the same ODBC driver in MS Access, the table can be linked, column_names are shown, but retrieving data generates error message: ODBC - call failed [MonetDb][ODBC Driver 1.0]TODO: column names of level >= 3 (#0) What can you recommend? Thanks for your help, regards, Klaas

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[MonetDB-users] Types oid, size_t.
by Guillaume Yziquel 03 Feb '10

03 Feb '10

Hi. I've been wanting to wrap up oids into OCaml, and I'm wondering a few things about the following statement in gdk.mx: > @item oid: > Unique @strong{long int} values uses as object identifier. Highest bit cleared always. > Thus, oids-s are 31-bit numbers on 32-bit systems, and 63-bit numbers on 64-bit systems. Moreover, the oid type is typedefed in the following way: > #ifdef MONET_OID32 > #define SIZEOF_OID SIZEOF_INT > typedef unsigned int oid; > #else > #define SIZEOF_OID SIZEOF_SIZE_T > typedef size_t oid; > #endif I understood that MONET_OID32 was the exception rather than the rule, so I'm assuming, for now, that oid is size_t. But then, I'm wondering why the highest bit is always cleared. Moreover, OCaml has a way to deal with their integers which is rather peculiar. They are long ints, but the lowest bit has a peculiar meaning. If the lowest bit is 0, then this long int is in fact a pointer to an OCaml value in the OCaml heap. If the lowest bit is 1, then shift the value one bit, and you have the Ocaml integer. This scheme takes advantage of the alignement of OCaml values in the OCaml heap. So ocaml integers are 31-bit on 32-bit systems, and 63-bit on 64 bit systems. The difference is that the lowest bit is set, whereas it's the highest bit that is cleared for oids. Therefore, to convert oids to ocaml ints and conversely, I wrote: > #define ocamlmonetdb5_Val_oid(x) ((value) ((((oid) x) << 1) + 1)) > #define ocamlmonetdb5_Oid_val(x) (((oid) x) >> 1) Two questions: -1- This seems to work, but I'd appreciate if you could double-check this. Just to check if I understood correctly the bit layout of oids. -2- I'm wondering why the highest bit of oids is always cleared. This doesn't seem to be implied by the fact that oids are typedefed size_t. So what's the rationale? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] sql date
by dariuszs 02 Feb '10

02 Feb '10

Hi, Is there any documentation on how to manipulate dates (add/subtract months, days, years)? Running query: sql>select date '1900-01-01' + interval '100' year; Produces error: Incorrect interval (3>1)..... Thanks. Dariusz.

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[MonetDB-users] size_t vs. var_t on Windows
by Alex Bo. 31 Jan '10

31 Jan '10

Hi, I've been trying to build the MonetDB5 module from the Feb2010 branch from CVS on Windows. However, I am getting this: .\..\..\..\..\src\modules\kernel\group.mx(1330) : warning C4267: '=' : conversion from 'size_t' to 'var_t', possible loss of data .\..\..\..\..\src\modules\kernel\group.mx(1330) : warning C4267: '=' : conversion from 'size_t' to 'var_t', possible loss of data This did not happen in the November releases on Windows. Any ideas on how to approach this? Do I need to use some special flags? Thanks. -- View this message in context: http://old.nabble.com/size_t-vs.-var_t-on-Windows-tp27396298p27396298.html Sent from the monetdb-users mailing list archive at Nabble.com.

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[MonetDB-users] MonetDB/XQuery stability problems w/ shredding
by Xander Schrijen 29 Jan '10

29 Jan '10

Hi list, I'm using MonetDB/XQuery to run queries on sets of XML documents of all kinds (build files, process descriptions). These sets can range from a few dozen to a few thousand documents, so the speed of MonetDB can be a real boon. However, when shredding these documents there may be a few errors. Sometimes a namespace URI is reported as not well formed, sometimes shredding 'hangs' (esp. when using the batch-import method from the manual), sometimes I can't find a reason. After such an error, the database seems to be corrupted. Sometimes queries for which collections are in the database give errors, sometimes an XPath query doesn't finish. In most cases, the ERROR=.... from mclient doesn't give a proper error (ascii garbage). I reallize these reports are vague. However, even though this happens a lot, reproducing the exact sequence can be hard. (Importing a few 100 documents, waiting for the import error to occur, using the right query to trigger the error...) But as it is now, I don't even know if these things are known, have work-arounds, or require fixing the xml documents upfront. Are there people on the list with experience with this that are willing to help me out? Regards, Xander.

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[MonetDB-users] Announcement: New Nov2009-SP2 bugfix release of MonetDB suite
by Sjoerd Mullender 28 Jan '10

28 Jan '10

The MonetDB team at CWI/MonetDB BV is pleased to announce the Nov2009-SP2 bug fix release of the MonetDB suite of programs. More information on this release will be available at <http://monetdb.cwi.nl/Development/Releases/Nov2009/>. Fixes include: - No need to require bash for running the *-config scripts. (SF bug #2914563) - MonetDB5 development package now contains all development include files. (SF RFE #2929558) - Added support for compiling on OpenBSD (contributed, i.e. not tested by us). - General code improvements, partly inspired by running Coverity Scan. - mclient -D will exit with a non-zero exit code if dumping failed. (SF bug #2925674) - The Python interface now uses the same socket options as the C version, giving a boost in performance. (SF bug #2925750) - Fixed a bug in the Python interface to deal with fields with embedded newline characters. (SF bug #2917219) - Added initial support to the Python client interface for specifying the encoding. - Fixed a bug in execute argument parsing in Python interface. - Added missing .sql files to the Windows installer. - In MonetDB/SQL, fixed bug in not(invalidtable). (SF bug #2927174) -- Sjoerd Mullender

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[MonetDB-users] OCaml-MonetDB is working.
by Guillaume Yziquel 22 Jan '10

22 Jan '10

Hello. I've managed to pull together, in my scarce free time, an OCaml binding for MonetDB. It is now working and I have written a very simple MAL client for an embedded database: > yziquel@seldon:~/git/ocaml-monetdb5$ utils/malclient.native > io.print(1); > 1 > io.print(2); > 2 I've got a small question concerning MAL. As I see it, MAL is currently a human-readable language. Is there somewhere in the MonetDB system a place where it is compiled to a more space-efficient representation? Or is interpreted as such? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] MonetDB XQuery Bulk Load / Bulkload
by Alexander Koglin 21 Jan '10

21 Jan '10

I have currently installed a version of MonetDB XQuery for Linux and want to bulkload data like this: http://monetdb.cwi.nl/XQuery/Documentation/Bulk-Loading-a-Collection.html#B… For that purpose, I used the following command inside the Client: for $d in doc("/monetdbfiles.xml")//doc return pf:add-doc(fn:concat($d/@path,$d/@name), fn:string($d/@name), "abap10k", 0) <> It references the following, definitely existing XML file: <dir> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCDEF"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCIMP"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CCMAC"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CI"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM001"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM002"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM003"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM004"> <doc path="/home/epic/tarari_svn/benchmarks/abap/ABAP/" name="ACL_AUNIT_RESULT==============CM005"> </dir> But unfortunately an error is thrown (I also tried it unter Windows and it was the same): MAPI = root@localhost:50000 QUERY = for $d in doc("/monetdbfiles.xml")//doc ERROR = !ERROR: err:FODC0002, Error retrieving resource (no such document "/monetdbfiles.xml"). What could be the reason for that?

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[MonetDB-users] compression
by Jason Kinzer 20 Jan '10

20 Jan '10

Hi, Are there any plans on the horizon to roll compression into Monet? The X-100 project looked really interesting in this regard, but as I understand it, that work has been transferred into VectorWise. If there are no plans, is this because it's completely antithetical to the monet architecture (from the papers it seems like X-100 was, to some degree at least, 'integrated' in), or more due to lack of resources? My motivating example here is OLAP: I frequently have 1 relatively large fact table and then many much smaller dimensional tables. If optional compression were available, it we be nice to compress all or some of the BATs for the fact table columns and then have the others work as usual. (Well, at least this sounds good, maybe it makes no sense). Another motivation is there seems to be a lot of anecdotal evidence for companies moving from larger big iron servers to more numerous, smaller machines - so it would be really nice to have this capability for more memory constrained settings. I understand on a basic level how compression conflicts with the relatively simple approach monet uses to load BATs (e.g. memory map), but, dwelling in ignorance, I blithely assume there could be some solution not as complex as X-100 if one were to accept a significant performance cost. For example: decompressing BAT data on the fly as part of a BATiterator. I probably don't have the skills to implement even a basic on-the-fly decompression approach like this, but just wondering aloud: how hard a problem is this? Thanks, Jason

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[MonetDB-users] manually setting gdk_nr_threads to N?
by Nafees Ur Rehman 19 Jan '10

19 Jan '10

Hi, I am using Windows 2003 with two core processors configures, and the gdk_nr_threads does not show the 2nd processor. Can you tell me how can I set that manually? Regards Nafees Ur Rehman

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[MonetDB-users] Standard Deviation tips and hints request
by Dennis Forbes 17 Jan '10

17 Jan '10

Hi all. While it's possible to calculate the stddev with an aggregated cross join, is there perhaps a better way? Any tips or hints on where I should look? Can this be done in MIL or some other tactic to provide a more straightforward, better performing experience? I searched the web before asking and all I've found are unanswered questions, however I would really like to solve this even if it includes extending the system. Dennis W. Forbes Vastardis Capital Services 41 Madison Avenue, 30th Floor New York, NY 10010 P: 646-230-0933 F: 212-243-5251

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[MonetDB-users] mapi_query with MAL code?
by Guillaume Yziquel 17 Jan '10

17 Jan '10

Hello. I've been using an embedded SQL with moderate success with my OCaml binding. Essentially passing the SQL statement through the mapi_query() function call. I would now like to try out some MAL code in a similar setting: embedded MonetDB, code passed via mapi_query(). Could someone provide me with a simple "Hello world" MAL code to try? For now, all I've been able to achieve with MAL are segfaults... All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] native socket protocol vs mapi
by Andy Chambers 16 Jan '10

16 Jan '10

Hi, I want to be able to use monetdb from common lisp and was looking at the other language bindings for clues on how to write one for cl. Python and Ruby seem to communicate using a socket rather than use the C api. However, in common lisp it's relatively easy to use C bindings (though CFFI) so I'd rather use them if I thought they were going to continue to be supported. Are there any other factors I should consider in deciding which API to use? Many Thanks, Andy

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[MonetDB-users] Star Schema Benchmark: Can't load SF 5 ou SELECT, LINE_READ Crash
by Rui Anastácio 12 Jan '10

12 Jan '10

Hello, I Have Ubunto 9.10 Karmik Koala installed. On top of this I have installed MonetDB latest version (same problem with previous one). I'm working with Star Schema Benchmark (SSBM). For Scale Factor 1 and 3 I can load the data. For SF 5 our above I get READ_LINE error when loading LINEORDER table. Also when running select Q4.1 I also get the same error and the server crashes. Anyone as a clue? Thanks Rui A.

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Re: [MonetDB-users] monetdb_sql/mal() ?
by Guillaume Yziquel 12 Jan '10

12 Jan '10

Jason Kinzer a écrit : >> >> Besides, It would seem to overlap with Mauricio's work which already >> provides some parsing from his OCaml algebra to SQL. But the thing is, >> you've got the SQL string created at OCaml compile time. I may be wrong about this compile time assertion. It now seems to me that this is runtime. In which case, it would make sense to map Mauricio's relational algebra to MAL's relational algebra. >> What would be nice >> is to have the SQL -> MAL compilation also happen at the same time you >> compile the OCaml program. >> >> (Moreover, it seems to me that MAL comes in two flavour: a human-readable >> one and a machine readable one. Is that correct? If yes, I'm aiming at the >> machine readable one.) >> >> How easy would that be? Do you need a running embedded server for that, or >> simply a subset of the functionalities of the MonetDB shared libraries? > Ah, I see now, so you're talking about actually writing a SQL->MAL compiler > as part of that existing Ocaml SQL frontend (sort of cut out the > "middle-man"). Yes. > That sounds neat, but bear in mind that could be tantamount > to re-writing the existing Monet SQL frontend, depending on your goals In fact, I would like to do an OCaml/C binding to the SQL -> MAL compilation that is already done in MonetDB. This seems to me the least effort path. But I'd like to know where in the code is this compilation / conversion from SQL to MAL done. > - so I let you draw your own conclusions. Try doing an "explain" on various SQL > statements to see the generated MAL. Sorry, I'm quite new to MonetDB and still having a hard time with the documentation. What is this "explain" thing I should be doing? > I would say writing a very naive, > minimal SQL translation is not easy but certainly within raeach. Here > someone other than I should comment, but I think most of the complexity of > the existing frontend lies in the optimization passes, tx handling, > approaches to handle datasets that won't fit in memory, etc. Rewriting an SQL -> MAL translation is not my goal. Reusing an existing one would be one my goals. All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] monetdb_sql/mal() ?
by Guillaume Yziquel 11 Jan '10

11 Jan '10

Hello. I've been looking at Debian packages, and the followig things struck me: -1- You have two shared libraries: libembeddedsql.so and libembeddedmal.so which are distributed, but there's only headers for the *sql.so one. You have to write your own for the *mal.so one. -2- In the source, there are two libembeddedclient.c.in files: one for sql, one for mal. The one for sql contains a monetdb_sql() function call. The one for mal does not. Is there a good reason for this? Or is it simply the way it currently is? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/

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[MonetDB-users] problems with the interpretation of the query history
by Gerrard_56 10 Jan '10

10 Jan '10

Hi. I’m a new MonetDB user and I use the MonetDB server v5.14.2 with the MonetDB/SQL module v2.32.2 on a windows xp platform. I have some problems with the interpretation of the queryhistory and the callhistory. My first question is: What is the meaning of the parse and the optimize attributes in the queryhistory. Is the optimize attribute used to store the time which the front-end needs to parse the sql statement into a mal plan respectively is the optimize attribute used to store the time used for the optimization done for the mal plan. I’m asking because couldn’t find an explanation in the sql manual. My next questions concern the xtime and the rtime attributes of the callhistory. Sometimes for some queries the xtime is 0 usec. Does this indicate that the query was already executed once before and therefore there isn’t a preparation time needed for the result set? Sometimes for some queries only the rtime is 0 usec but the the xtime is > 0 usec. What does this means? There is a preparation time for a result set but there is no time needed to construct and return the result set to the user. For me this makes no sense. Sometimes there is the xtime and the rtime 0 usec. Does this mean that the query never runs in the database engine? Does somebody know the reason for this behavior? Lust but not least in the sql manual you can read that all storage is in K/M/G bytes. But where can I find out if K bytes M bytes or G bytes are used? Thank you for any help Gerrard (I apologize for any grammar and spelling mistakes in this posting but my English is not the best.) -- View this message in context: http://old.nabble.com/problems-with-the-interpretation-of-the-query-history… Sent from the monetdb-users mailing list archive at Nabble.com.

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