Get the SQL for an insert statement from ActiveRecord

build_insert_query.rb

# Builds an SQL insert query for a given record
#
# @param record [ActiveRecord::Base] Record used to build the SQL insert query
# @return [String] SQL insert query
def build_insert_query(record)
  columns = record.class.columns.reject { |col| col.name == record.class.primary_key }
  values = columns.map { |col| record[col.name] }
  insert_manager = Arel::InsertManager.new
  insert_manager.into(record.class.arel_table)
  insert_manager.insert(columns.zip(values)).to_sql
end

user = User.new(first_name: "John", last_name: "Doe")
build_insert_sql(user) # => SQL instert query