magic.rb

# open a hash of FasterCSV generators
data = { :table1 => nil, :table2 => nil, :table3 => nil, :table4 => nil }
data[:table1] = FasterCSV.generate do |data[:table1]|
data[:table2] = FasterCSV.generate do |data[:table2]|
data[:table3] = FasterCSV.generate do |data[:table3]|
data[:table4] = FasterCSV.generate do |data[:table4]|

# do stuff with it

# close them, rewriting the data to CSV inside the same hash
end
end
end
end