Can we split and join the large text files - filesplitting

I need to split large text files around 10 GB into multiple text files (mostly 1gb files)
and join those same text files into one file.

If you have split command then try this,
Example:
split -b1024 your_large_file.txt sample_prefix
It will split the large file and produce the list of files with 1024 bytes.
Join:
cat sample_prefixaa sample_prefixab sample_prefixac > final_org_largefile.txt
It will concatenate the contents of the spitted files and produce the single file.
Note: Linux will have split command. But, I don't know about GNUwin32.

Related

How can I split content of a file to two different files using shell script

I want to split a file into two parts
I want to split a single file into two different files using shell script.
You can use linux split command, either by lines split -l<num_of_line> <file_name> or by size split -b<size><K|M|G> <file_name>.
For example: split -l100 a.txt will split each 100 lines into separate files.
Here is a link you can see more examples and all details.

awk command does not halt on windows for merging large csv files

I am executing the following awk command on Windows 10.
awk "(NR == 1) || (FNR > 1)" *.csv > bigMergeFile.csv
I want to merge all csv files into a single file named bigMergeFile.csv using only the header of the first file.
I successfully tested the code on small files (4 files each containing 5 cols and 4 rows). However, the code does not halt when I run it on large files (10 files, each with 8k rows, 32k cols, approximate size 1 GB). It only stops execution when the space runs out on hard drive. At that time, the size of resultant output file bigMergeFile.csv is 30GB. The combine files size of all input csv file is 9.5 GB.
I have tested the code on Mac OS and it works fine. Help will be appreciated.
My guess: bigMergeFile.csv ends in .csv so it's one of the input files your script is running on and it's growing as your script appends to it. It's like you wrote a loop like:
while ! end-of-file do
read line from start of file
write line to end of file
done
since you're doing basically a concat not a merge, set FS = "^$" to it won't waste time attempting to split fields you won't need anyway.

How to aggregate the result of bash sort on multiple files into a single file?

I have a ~90GB file. Each line consists of tab-separated pairs such as Something \t SomethingElse. My main goal is to find the frequency of each unique line in the file. So I tried
sort --parallel=50 bigFile | unique -c > new_sortedFile
which did not work due to the file size. Then I split the original big file into 9 parts (each 10 GB) then the same command worked for each file separately.
So my question is how can I aggregate the result of those 9 files into a single file in order to have the same result of the bigFile?

split the multiple lines files into small files based on the content

I want to create a script to split large files into multiple files with respect to line numbers. Mainly if a file is getting split there should be a complete line at the end / beginning.
No partial line should present in any of the split files.
split is what you might be looking for.
split --lines <linenumber> <file>
and you will get a bunch of splitted files named like: PREFIXaa, PREFIXab...
For further info see man split.

Is there a better split function for terminal?

I'm trying to split a very big CSV file into smaller more manageable ones. I've tried split but it seems that it tops out at 676 files.
The CSV file I have is in excess of 80mb and I'd like to split it into 50 line files.
Note by better I mean one that uses a numbering structure instead of split's a-z sequencing.
split is the right tool, the problem is that the suffix is only 2 long 26^2 = 676, if you make it longer you should be fine:
split -a LEN file
Use 'cat' to number each line and pipe the output to 'grep' with params to only print n lines

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