Given a column of data resembling the following: col 2 3 4 5 11 12 13 14 15 16 17 18 19 23 32 33 34 35 36 37 I need a query to find the contiguous ranges within this column, in this case returning the result set: start, end 2, 5 11, 19 23, 23 32, 37 I have one solution that joins the table against itself and does (among other things) a subselect looking "not exists col +1" and "not exists col -1" on the two instances of the table to find the start and end. This is, as you might guess, is not very efficient (my actual data is some 6 million+ rows) and I'm guessing there has to be something more efficient with windowing or possibly grouping on min and max (though I can't see how to make sure they are part of a contiguous set). Anyone have any ideas? -- Peter Hunsberger -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
