>>>>> "RP" == Rajeev Prasad <[email protected]> writes:
RP> hi, you can try this: first get only that field (sed/awk/perl)
RP> whihc you want to sort on in a file. sort that file which i assume
RP> would be lot less in size then your current file/table. then run a
RP> loop on the main file using sorted file as variable.
RP>
RP> here is the logic in shell:
RP>
RP> awk '{print $<filed-to-be-sorted-on>}' <large-file> > tmp-file
RP>
RP> sort <tmp-file>
RP>
RP> for id in `cat <sorted-temp-file>`;do grep $id <large-file> >>
sorted-large-file;done
have you thought about the time this will take? you are doing an O( N**2
) grep there. you are looping over all N keys and then scanning the file
N lines for each key. that will take a very long time for such a large
file. as others have said, either use the sort utility or do a
merge/sort on the records. your way is effectively a slow bubble sort!
uri
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