2010/11/12 Dmitriy Igrishin <dmitigr@xxxxxxxxx>: > Well, it's possible to create GIN indexes on arrays of built-in data types > without extra efforts, because of "GIN" access method has defaul > operator class. But it's not true for GiST: now you have a true :) you need to install intarray contrib module for GiST Pavel > > SELECT am.amname AS index_method, opc.opcname AS opclass_name > FROM pg_am am, pg_opclass opc > WHERE opc.opcmethod = am.oid AND am.amname = 'gist' > ORDER BY index_method, opclass_name; > > ÂgistÂÂÂÂÂÂÂÂ | box_ops > ÂgistÂÂÂÂÂÂÂÂ | circle_ops > ÂgistÂÂÂÂÂÂÂÂ | point_ops > ÂgistÂÂÂÂÂÂÂÂ | poly_ops > ÂgistÂÂÂÂÂÂÂÂ | tsquery_ops > ÂgistÂÂÂÂÂÂÂÂ | tsvector_ops > > With hstore I don't need to care about it at all. > > But thank you very much to points me about indexes on arrays ! > > 2010/11/12 Pavel Stehule <pavel.stehule@xxxxxxxxx> >> >> 2010/11/12 Dmitriy Igrishin <dmitigr@xxxxxxxxx>: >> > Hey Peter, >> > >> > Unfortunately, there is no indexes on arrays (only on expressions). >> >> there are indexes on arrays - you can use a GiST, Gin indexes. >> >> regards >> >> Pavel >> >> >> > With hstore we can easily create GiST index for effective access. >> > >> > 2010/11/12 Peter Bex <Peter.Bex@xxxxxxxxx> >> >> >> >> On Fri, Nov 12, 2010 at 10:17:50AM +0300, Dmitriy Igrishin wrote: >> >> > Hey Mark, >> >> > >> >> > Yeah, I can't imagine an entity in a real project even with more than >> >> > 100 >> >> > columns. Its rare case. >> >> > But if you entities (rows/tuples) of some class (table) can contains >> >> > variable >> >> > set of columns (properties) you can look at hstore contrib module. >> >> >> >> What can also work extremely well is storing the data in an array. >> >> If you need to access the array based on more meaningful keys you could >> >> store key/index pairs in another table. >> >> >> >> This approach only works well if you have multiple arrays with the same >> >> layout. ÂYou probably also need to build up your query dynamically if >> >> you need to access variable numbers of datapoints. >> >> >> >> Cheers, >> >> Peter >> >> -- >> >> http://sjamaan.ath.cx >> >> -- >> >> "The process of preparing programs for a digital computer >> >> Âis especially attractive, not only because it can be economically >> >> Âand scientifically rewarding, but also because it can be an aesthetic >> >> Âexperience much like composing poetry or music." >> >> Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â-- Donald Knuth >> >> >> >> -- >> >> Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) >> >> To make changes to your subscription: >> >> http://www.postgresql.org/mailpref/pgsql-general >> > >> > >> > >> > -- >> > // Dmitriy. >> > >> > >> > > > > > -- > // Dmitriy. > > > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
