Nurullah Akkaya wrote:
It is not quite clear to me what you are trying to achieve. Why do
you want a sequential read? Scanning the entire table of 100 million
records should take longer time than looking up a record using a
index on wordid. Have you retrieved the query plan and made sure the
index on wordid is used? Or are you talking about doing a lookup of
many different wordids in sorted order?
i did not meant sequential scanning of the whole table i meant disk
i/o( bottom paragraph explains it )
yes i checked the query plan and derby uses index to lookup records
and index look up checks only two index pages. so i came to the
conclusion that most of the time is lost making random i/o request for
the data thats why i am trying to keep the table sorted. since
sequential hard disk access is much faster than random i/o .
You should probably be looking at Lucene or perhaps Jackrabbit for this
kind of use case. Lucene is designed for text indexing and I have found
it to be very fast and efficient.
