Hi, I'm still catching up on emails as I was on a short vacation the last few days.
> Spatial feature would require at least one library dependency JTS topology suite, is this a problem for trunk development ? As far as I see, the JTS is LGPL. But as long as the source code of JTS is not included within H2 it should be fine I guess. It would be a runtime dependency only, so the users would have to deal with the license issue. Long term, I would like use the R-Tree in the MVStore; but it doesn't have many features yet and is not yet integrated with the database itself, so I suggest to not use it for your work yet. About the R-Tree in the MVStore: well, see for yourself: http://h2database.com/html/mvstore.html#r_tree - it's not fully loaded in memory. Regards, Thomas On Fri, Apr 19, 2013 at 3:34 PM, Brian Craft <[email protected]> wrote: > This is interesting. Is the entire R tree loaded into memory at once, or > can it be partially loaded as needed? > > I have seen some blog posts about using mysql spatial features, which > found that it loads the whole R tree into memory, and consequently has some > very poor performance features for large tables, or large numbers of tables. > > UCSC has developed a different technique for genomic spatial queries, > where they calculate something like a fixed R tree bin ID (fixed meaning > it's the same bins for every dataset, it doesn't create bins based on the > data) for each feature, and store the bin ID in a B-tree indexed column. I > believe this doesn't require loading the whole index into memory at once, > though it does require some application code to compose the queries on the > bin column, because they are moderately complex, and can't be encapsulated > easily into a sql function or view. > > > On Friday, April 19, 2013 2:38:29 AM UTC-7, Nicolas Fortin (OrbisGIS) > wrote: >> >> Ok, the patch is done for OSGi and it works well. >> >> I should write Unit test but I don't find *unit test* on OSGi activator. >> I'm using IntelliJ, how do you create a valid project with H2 source ? >> >> How it works : >> >> The H2 Bundle Activator register into org.h2.Util.Utils an object that >> handle a specific kind of binary class name. This specific binary class >> name follow this structure >> >> "BundleSymbolicName:**BundleVersion:JavaBinaryName" >> >> I don't find a standard way to describe such kind of structure. I could >> use Bundle Id (int) but this identifier can change after framework restart, >> and it is too opaque. >> >> This extended name allow OSGi developers to still using the "CREATE >> ALIAS" Sql query without doing any Java operation, neither deal with h2 >> packages. >> >> I'm working now on H2 trunk, still trying to figure out what is the best >> strategy for h2 spatial. >> >> Thank for you support. >> >> -Nicolas >> >> Le jeudi 18 avril 2013 17:12:59 UTC+2, Nicolas Fortin (OrbisGIS) a écrit : >>> >>> Thank your for the answer. I will work on the patch, trying to not break >>> anything. And I will send another patch for maven local build that do not >>> read the good version of the library (got stuck on home made build system). >>> >>> I will release also H2 Spatial OSGi integration and unit testing >>> projects also. >>> >>> For license I will see with my boss Erwan. Spatial feature would require >>> at least one library dependency JTS topology suite, is this a problem for >>> trunk development ? May be an optional build to enable spatial feature ? >>> >>> Best regards, >>> >>> -Nicolas >>> Le jeudi 18 avril 2013 16:27:30 UTC+2, Noel Grandin a écrit : >>>> >>>> >>>> >>>> On Thursday, 18 April 2013, Nicolas Fortin (OrbisGIS) wrote: >>>> >>>>> We are using H2 in an OSGi environment. >>>>> >>>>> I search an alternative to CREATE ALIAS in order to provide to h2 the >>>>> java Class. >>>>> >>>>> Maybe by calling something like org.h2.util.Utils.**addUserClass("Class >>>>> name",Class<?> userClass); >>>> >>>> >>>> >>>> Are yes, I see your problem. In an osgi context the db does not know >>>> which class loader to use when loading the alias. >>>> >>>> For now I suggest you patch such a method in yourself. If you can't go >>>> that, I will send you a patch next week. (I'm at a conference this week) >>>> >>>> >>>> >>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> -- > You received this message because you are subscribed to the Google Groups > "H2 Database" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/h2-database?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
