Merging 2 Files

[dayankoven]

Hi everyone,

I have a situation in which i need to merge 2 files, File A and File B. Both files are fixed length files and the file format is identical. The only problem is that the files are really very very huge. Each file is has about 2 million records. Each line is about 528 bytes. So, i'm looking at about 10560 MB of data per file.

I believe we can invoke a CAT command

CAT File A File B > File C.

I've read somewhere that the CAT command doesn't work well for huge files.

Is there a way i can achieve this merging in a very fast and efficient way via UNIX scripting.

Thanks in advance for all the help.

 

[rkrishnan]

while read oneLine
do
echo $oneLine >> file_C
done < file_A

while read oneLine
do
echo $oneLine >> file_C
done < file_B

The above lines in a script should do the job for you.

 

[PHV]

rkrishnan, the goal is efficient way, so doing a shell read line by line is certainly not an option.
dayankoven, you may consider something like this:
cp "File A" "File C"
cat "File B" >> "File C"

Hope This Help, PH.
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