On Wed, January 20, 2010 3:09 pm, Oleg Kobchenko wrote: > There is type "binary" (similar to varchar), which > is intended for things like images etc. > > So you should be able to store values like J nouns > (of any shape and type, even boxed, in external binary form) > or linear array of scalar type (e.g. list of doubles), > and then save and restore accordingly.
Thanks, Oleg. That sounds nice, but testt3=: Create__testd 'id3' InsertCols__testd 'id3'; 0 : 0 timeseries binary ) ShowCols__testd 'id3' +-----+----------+------+------+------+---------+ |table|column |type |unique|parent|parentkey| +-----+----------+------+------+------+---------+ |id3 |timeseries|binary|0 | | | +-----+----------+------+------+------+---------+ Insert__testd 'id3';<i. 3 4 |101 Invalid data rank: throw | throw'101 Invalid data rank' Is that what you would expect? Did I not understand what binary means? > While you explore this, it would be good to make it into > an illustrative example to append to JDB test scripts. Agreed. Assuming my manager doesn't have a problem with it, I could do that. > The above won't allow any in-DB time series analysis, since > the data is opaque that way. An alternative is to > store the data relationally, in hope that the inverted > representation will already be optimal enough. This would > allow some TS logic in queries. There isn't much functional > support in existing J-QL, but this use case may present > a good opportunity. Say more about "storing the data relationally." Do you mean store each datapoint in the series as a record? I figured that would be hard to deal with (select * from series1 where time in (start, end) in informal SQL), and, as the times don't necessarily have meaning between series, I figured that wouldn't help much. Perhaps you have something different in mind. What I'll likely be querying is something like select seriestype1 from table where attribute1 = x and attribute2 = y; to get an array of series that I can then process outside of the SQL paradigm. > Do you have a roster of time series analysis you plan to use? I'll be collecting energy-related data. > E.g. select a fastest growing quantity in a given month, maybe. I could certainly dummy up something as an example. Thanks, Bill ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
