I have this database (1MB) that I know has duplicate lines. The database layout is ID,NAME,ADDRESS,EMAIL How do I sort it remove duplicates and have it print out into a new file. 
#!/usr/bin/perl -w

open(INF,"db.txt");
@data = <INF>;
close(INF);

@sd = sort(@data);

...what do I use to remove duplicates...

open(OUTF,">outdb.txt");
print OUTF;
close(OUTF);

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In reply to Remove Duplicate Lines by dcb0127

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