AltME: Databases

Messages

Gregg
Thanks for the info Tomas.
TomBon
crawled html/mime embedded documents/images etc. as plain compressed source (avg. 25kb) and 14 searchable metafields (ngram) to train different NN types for pattern recognition.
Maxim
thanks  :-)

MaxV
I have a problem with RebDB: how works db-select/group?
Example:
>> db-select/where/group/count [ID title post date]  archive  [find post "t" ] [ID]
** User Error: Invalid number of group by columns
** Near: to error! :value
Endo
Don't you need to use aggregate functions when you grouping?
* when you use grouping.
Scot
I use the sql dialect like this:
sql [select count [ID title post date] from archive group by [ID title post] where [find post "t"]]
The trick with this particular query is the that the "count" selector must have exactly one more column than the "group by" selector.  The first three elements [ID title post] are used to sort the output and the last element [date] is counted.
output will be organized:
    ID  title   post    count
I would like to be able to include other columns in the output that are not part of the grouping or count, but I haven't figured out how to do this in RebDB.  I have used a parse grammar on the output to achieve the desired result.
I would also like to query the results of a query, which I haven't figured out how to do so without creating and committing a new database.  So I have  used a parse grammar to merge two queries.

Pavel
SQLite version 4 announced/proposed. The default built-in storage engine is a log-structured merge database instead of B-tree in SQlite3. As far as I understand the docs This store could be usable standalone or use SQL frontend. Google to SQLite4.
Kaj
Cool

Endo
I cannot see any announcement on the sqlite.org web site? SQLite 3.7.17 is the latest and recommended version?
Kaj
I saw code last year, but it's probably still in deep development

Pavel
Endo as I wrote google for SQLite4. direct link is: http://sqlite.org/src4/doc/trunk/www/design.wiki. There is a mirror of souces at https://github.com/jarredholman/sqlite4 also.

Pekr
Has anyone tried to work with ODBC under R3? I somehow can't load following ODBC driver DLL: https://github.com/gurzgri/r3-odbc
Or differently, has anyone worked with excel files via ODBC, using either R2 or R3? I tried Graham's code, which works for .xls files, but not .xlsx files. When I convert my file to .xls, R2 returns - not enough memory :-(
p: open [
     scheme: 'ODBC
     target: "Driver={Microsoft Excel Driver (*.xls)};DriverId=790;Dbq=c:\path-to-file\file.xls"
]
conn: first p
insert conn "select * from [Sheet1$]"
result: copy conn
As for R3 - maybe there was also some other R3 ODBC extension, somehow can't find it ....
hmm, found it, but no more available - http://www.rebol.org/ml-display-thread.r?m=rmlXJPF ... the problem with gurzgri DLL is, I can't somehow import it with any R3 version ...
Kaj
What you found looks to be the latest version of that
I've also had loading problems with R3 extensions on Linux that worked before. Sometimes you seem to need an older R3, sometimes a newer
If all else fails, recompile the C code

Last message posted 95 weeks ago.