How to concatenate a large number of rows by summing data across identical rows?

Question

MySQL

Hello!
Initial data:
50 csv-files in the format
документ;колонка1;колонка2;колонка3
There are about a billion lines in all files.
Documents can be repeated both within one file and between several files (the number of identical documents is not known in advance).
Necessary:
​​Combine all files into one (or into one database), summing up the data in column1, column2 and column3 for identical documents.
Can you please tell me how it can be done in the shortest time?
I put SQL tags, because I think that one cannot do without some kind of SQL server.

Answer 1

Perhaps it is worth starting a conversation with a programming language?)

Answer 2

It will be faster to do LOAD DATA INFILE dev.mysql.com/doc/refman/5.1/en/load-data.html and import directly from CSV.
You can try engine=ARCHIVE if the operation is a one-time operation. There will be a greater chance of getting into memory with the next GROUP BY