Merge some parts of a split tar.gz file Linux command - linux

Question

I have a large tar.gz file (approximately 63 GB) on a linux server. This file has about 1000 compressed csv files. I need to save the data of csv files in a database.
I can't extract whole file in one go due to limited space on the server. So I split the tar.gz file into 5 parts (4 parts of 15 GB and 1 of 3GB) but did not merge all of them as the server won't have any space left when extraction would be done. I merged the first two parts to make a new tar.gz file and extracted the csv files from that.
When I tried to merge the last 3 parts, it did not make a valid tar.gz file and that file could not be extracted. This problem was not because of server space because I deleted the files that were no longer required after extraction from first two parts.
Is there any way through which the last 3 parts of the split tar.gz file can be merged in a valid tar.gz format and then extracted?
Command used to split :
split -b 15G file.tar.gz parts
Command used to merge :
cat parts* > combined.tar.gz
Command used to extract :
tar zxvf file.tar.gz -C folderwhereextracted

Answer 1

You can use short shell script:
#/bin/sh
path='./path'
list="$path/*.tar.gz"
for file in `ls ./da/*.tar.gz.*`
do
let i++
if [[ -f $(find $path/*.tar.gz.$i) ]]
then
echo "file $path/*.tar.gz.$i found."
list="$list $path/*.tar.gz.$i"
else
echo "file $path/*.tar.gz.$i not found!"
fi
done
cat $list > full.tar.gz
tar zxvf ./full.tar.gz -C $path
# rm -rf $list
Put your path to variable with the same name.
Uncomment last line to remove source files after untar.