how to efficiiently select first or last rows from a KDB table stored on disk -


for in-memory table, can use sublist or take syntax retrieve first x, last x elements.

how efficiently on-disk table may large? constraint don't want cache data table memory run query.

.q.ind - takes table , (long!) indices table - , returns appropriate rows http://code.kx.com/wiki/dotq/dotqdotind


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