Ruby CSV prevent appending header

Question

While I'm appending data to csv in a loop headers also getting appended in csv file, for example consider below query

10.times do 
   CSV.open("file_name", "ab", write_headers: true, headers: ["team", "points"]) do |csv|
     csv << ["SRH","20"]   
   end
end

Resulting CSV will have alternate headers and alternate values. How to prevent appending headers multiple times? Thanks in advance.

You're opening the same csv file in every loop, do you definitely want to do that? — Max Williams
– Max Williams, Commented May 18, 2016 at 16:37
I don't mean I would append in loop, in runtime I would be appending to the existing file multiple times — Praveen Venkatapuram
– Praveen Venkatapuram, Commented May 18, 2016 at 16:45

Uzbekjon · Accepted Answer · 2016-05-18 17:30:28Z

1

You are opening up your csv file and adding data in a loop. You want to open your file ones and then add any data in a loop.

CSV.open("file_name", "ab", write_headers: true, headers: ["team", "points"]) do |csv|
   10.times do 
     csv << ["SRH","20"]   
   end
end

The output is:

team,points
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20
SRH,20

answered May 18, 2016 at 17:30

Uzbekjon

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