2
votes
3answers
640 views

How to edit the header of a huge CSV file in-place?

I have several huge CSV files in which I want to swap two column names. I do not want to modify/copy/rewrite the data. The operation is very cheap in C: fopen the file, fgets the header, fseek or ...
0
votes
1answer
470 views

how to convert line-delimited txt file into a spreadsheet file as tsv or xls

I have a huge amount of phone numbers (for example), one for each line in .txt file. 202898990 909090090 909090900 ... I want to put each number in a a cell (phone numbers in the same column). I ...
0
votes
2answers
4k views

How to force Excel to open CSV files with data arranged in columns

I generate a CSV file with an extension .csv in which every piece of data in one line is separated with a comma: 1,2,3,4 1,2,3,4 The file is sent via email and I want that when a customer opens it ...
10
votes
4answers
5k views

How to join two CSV files?

Suppose you have one CSV file with 2 fields: ID and email. You have another file with 2 fields: email and name. How can you produce a file with all three fields joined on email?