July 2013 - users-list

aggregate function in MAL
by Scott Mathieson 05 Jul '13

05 Jul '13

Hi, I am trying to create a simple aggregate function entirely in MAL and am now struggling at the final hurdle. I have created the aggregate function such that it aggregates across an entire table but in the sub aggregate function I can't work out how to link the group to data BAT (g) to the data. The aggregate is designed to simply collect a sample of the values from the named column and return them as a pipe delimited string value. Can anyone tell me how to use the 'g' bat to join to the 'b'… [View More] bat in the sub... aggregate function to get only the data rows for a specific group - currently I only get 2 rows of data per group even though I know that there should be 100k+ rows in each group? Here's the code: function bin_sample(b:bat[:oid, :any]):str; value := ""; bsamp := sample.uniform(b, 1000:wrd); barrier (h, t) := iterator.new(bsamp); tmp := "" + t; type := bat.getTailType(bsamp); test := str.startsWith(type, "str"); # Force the string type to be cast to a string or you just end up with numeric values barrier xxxx := test; tmp := str.str(t); exit xxxx; value := value + tmp; value := value + "||"; redo (h, t) := iterator.next(bsamp); exit (h, t); return value; end bin_sample; function subbin_sample(b:bat[:oid,:any_1],g:bat[:oid,:oid],e:bat[:oid,:any_2],skip_nils:bit) :bat[:oid,:str]; bn:=bat.new(:oid, :str); # check 'e' has some values - this is the list of group IDs in the head # 'g' is the group to the data BAT head ID mapping # 'b' is the data column BAT that we're aggregating over barrier (grpid, t) := iterator.new(e); # create a single row BAT of the group id we're processing bn_gid := bat.new(:oid, :oid); bat.insert(bn_gid, grpid, grpid); # join this to the GID->DATA map BAT to get the Group DATA oids b_g2dr := bat.reverse(g); b_gid2data := algebra.leftjoin(bn_gid, b_g2dr); grpval := ""; # Get the BAT of the actual data to be processed # # !!! HOW TO GET THIS TO WORK???????? # b_data := algebra.join(b_gid2data, b); grpval := bin_sample(b_data); # Store the result for this group bat.insert(bn, grpid, grpval); redo (grpid, t) := iterator.next(e); exit (grpid, t); return bn; end subbin_sample; Scott Mathieson, ________________________________ [View Less]

2 3

Failing to load a table
by Franck Routier 05 Jul '13

05 Jul '13

Hi all, I am trying to copy a table from a postgresql database into monetdb, but it fails, with monetdb filling the disks. I am using latest version of Monetdb (Feb2013-SP3) on Ubuntu Linux, with 32 GB Ram and SSD disks. To copy into Monetdb, I have a java program that runs mclient as: mclient --language=sql --databas=database --host=host --user=user /tmp/command.ctl with command.ctl : COPY nnn RECORDS INTO table FROM STDIN USING DELIMITERS'|', '\n', '\' NULL AS '' Then the Postgresql … [View More]

4 12

how are user defined function arguments passed ?
by integrity 05 Jul '13

05 Jul '13

Hi everyone, In http://www.monetdb.org/Documentation/Cookbooks/SQLrecipes/UserDefinedFuncti… In thesection about how to extend SQL with a simple scalar function to reverse a string step 3. Extension starts with a definitin of the MAL signatures. See the example given, or browse through the files in monetdb5/modules/mal/*.mal to get a glimpse on how to write them. The MonetDB kernel documentation provides more details. The file contains the MAL snippet: command reverse(ra1:str):str address … [View More]

1 0

Announcement: New Feb2013-SP3 Bugfix release of MonetDB suite
by Hannes Muehleisen 02 Jul '13

02 Jul '13

The MonetDB team at CWI/MonetDB BV is pleased to announce the Feb2013-SP3 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/>.

2 1