>>>>> "CD" == C DeRykus <[email protected]> writes:
CD> DB_FILE's module implements a 'hash-like' type BTREE
CD> based on the Berkeley DB API which can store/retrieve
CD> duplicate keys.
CD> $h{'Wall'} = 'Larry' ;
CD> $h{'Wall'} = 'Brick' ; # Note the duplicate key
CD> $h{'Wall'} = 'Brick' ; # Note the duplicate key and value
that is the heart of most ISAM (indexed sequential access method)
implementations. you can locate a key and then sequentially read records
from that point in sorted order. so duplicate keys are fine there. but
isam is not a common language feature. PL/I and cobol both supported
isam among other recond i/o systems. i don't know of any modern language
that directly supports isam (vs loading it via a module). most have
hashes or similar constructs as it is easy to implement, fast and they
have clean semantics. isam is wierd from a language view unless you
really need both direct and sorted sequential access. then use a module.
uri
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