in reply to Rapid text searches

It seems that you want to search for exact matches columns. If you know all the things you are looking for before hand, I would create a hash with the items you are searching for. So for instance if you are looking for 1101077781160, 1101077783669, and 1101077781182, I'd start off with
my %queries; $queries{$_} = 1 for qw(1101077781160 1101077783669 1101077781182);
Then I'd iterate over the file, split each line into fields, and test each field against the hash previously build.

This avoid multiple passes over the file (as you would with grep), or loading in the entire file into a hash.

And if I only looking for a single entry, perl script will still load everything into memory before it could look for the string I want?
You tell us instead of asking! You wrote the code. If you wrote your code it first slurps in the entire file, then the answer is yes. If you wrote your code it didn't, then the answer is no.