Find the records with the longest TEXT columns in a Rails + MySQL app's database tables.

longest_records.rb

ActiveRecord::Base.connection.tables.map { |table| 
  text_columns = ActiveRecord::Base.connection.columns(table).select { |c| c.type == :text }
  text_columns.map { |col|
    longest_record = ActiveRecord::Base.connection.exec_query("SELECT id, LENGTH(#{col.name}) as length FROM #{table} ORDER BY length DESC LIMIT 1").rows.first
    {
      table: table,
      column: col.name,
      record_id: longest_record.first,
      length: longest_record.last,
    }
  }
}.reject(&:empty?).flatten