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<H2><A NAME="s8">8. Fast access methods</A> </H2>
<P>The NoSQL operator 'nsq-search' may be used to execute one
of two fast access methods, binary or hashtable search.
<P>These methods are useful when the key field values of a
number of rows in an existing, large rdbtable is known
in advance, a common situation.
<P>One example of updating an rdbtable using these methods is
as follows. First, 'nsq-search' is used to quickly obtain a
new, small rdbtable consisting of the desired rows from the
existing, large rdbtable. Then 'nsq-ed' is used to update
the data in the new rdbtable, including generating new
rows, changing some rows, and marking certain rows for
deletion, if desired. The next stage would be to use
'nsq-merge' to combine the new and old rdbtables into a
new, large rdbtable, which will still be in sort order
(both the old rdbtable and the new, small one will still
exist for backup and/or journaling purposes). Note that
the last step could be done in the background.
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