How to remove a row from a CSV with Ruby

Question

Given the following CSV file, how would you remove all rows that contain the word \'true\' in the column \'foo\'?

Date,foo,bar
2014/10/31,true,derp
2014/10/         


        

Answer 1

You might want to filter rows in a ruby manner:

require 'csv' 
csv = CSV.parse(File.read(@csvfile), {
  :col_sep => ",", 
  :headers => true
  }
).collect { |item| item[:foo] != 'true' }

Hope it help.

Answer 2

You should be able to use CSV::Table#delete_if, but you need to use CSV::table instead of CSV::read, because the former will give you a CSV::Table object, whereas the latter results in an Array of Arrays. Be aware that this setting will also convert the headers to symbols.

table = CSV.table(@csvfile)

table.delete_if do |row|
  row[:foo] == 'true'
end

File.open(@csvfile, 'w') do |f|
  f.write(table.to_csv)
end