OK, I have searched "Super Search" for an answer to my issue, and this is what I have gleaned.

I have a process that looks through an extracted | delimited flat file via a while (FILEHANDLE) for a user id. When I find an id, I split it based on the pipe, examine the data, and based on values, move it into a specific keyed hash to be processed in another part of the program.

My issue is that the flat files are enormous (well for me) at +250 MBs. Is there a way that I can tell perl not to rescan the file each time the while loop goes through? 


#$userid already populated

open(FILE,"FILE.txt")

while(<FILE>) {
 
   if(/$userid/o) {
        chomp;
        #below is an example, there are actually 15 
        #variables coming out of this split.

        ($inv, $date, $amt)= split(/[|]/);

         #code to build hash.

    }

}

#processing of hashes

[download]

Is there anyway to tell perl, "hey, you have already gone through x lines, don't start over at the beginning of the file when you loop back through?

In reply to Search Efficiency by treebeard

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