pdbaugment - join rows from one FSDB files into another¶
pdbaugment provides a different mechanism for doing FSDB file joins
than the dbjoin command from the base perl FSDB package.
Specifically, pdbaugment is designed to read a single file entirely
into memory and use it augment a second one that is read in a
streaming style. pdbaugment has the advantage being faster because
it dose not need to do a full sort of both files, like dbjoin
requires, but has the downside of needing to store one file in memory
while performing the join. In general, the smaller file should be
used as the augment_file argument, and the larger as the
stream_file when possible. Matching keys in the augment file should
be unique across the file, otherwise only the second row with a give
key combination will be used.
Example input file 1 (myfile.fsdb):¶
#fsdb -F t col1 two andthree
1 key1 42.0
2 key2 123.0
3 key1 90.2
Example input file 2 (augment.fsdb):¶
#fsdb -F t col1 additional_column
key1 blue
key2 brown
Example command usage¶
$ pdbaugment -k two -v additional_column -- myfile.fsdb augment.fsdb
Example output¶
#fsdb -F t col1:l two:a andthree:d additional_column:a
1 key1 42.0 blue
2 key2 123.0 brown
3 key1 90.2 blue