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efficient_streaming

💾 Efficiently Process Large CSV Files​

When working with large CSVs, loading the entire file into memory can cause your app to crash. CSV.foreach reads the file line by line, yielding each row to a block without building a huge in-memory array. You can combine it with headers to get CSV::Row objects or skip headers for raw arrays.

require 'csv'

CSV.foreach('huge_data.csv', headers: true) do |row|
  # Process each row individually
  puts "User: #{row['name']}, Age: #{row['age']}"
end