Question

When I run

rails g model StripeCustomer user_id:integer customer_id:integer
annotate

I got

# == Schema Information
# Table name: stripe_customers
#  id          :integer(4)      not null, primary key
#  user_id     :integer(4)
#  customer_id :integer(4)
#  created_at  :datetime
#  updated_at  :datetime

Does it mean I can only hold up to 9,999 records only? (I am quite surprise how small a default size for keys is). How do I change default IDs to be 7 digits in existing tables?

Thank you.

Answer 1

While the mysql client’s describe command really uses the display width (see the docs), the schema information in the OP’s question is very probably generated by the annontate_models gem‘s get_schema_info method that uses the limit attribute of each column. And the limit attribute is the number of bytes for :binary and :integer columns (see the docs).

The method reads (see how the last line adds the limit):

def get_schema_info(klass, header, options = {})
  info = "# #{header}\n#\n"
  info << "# Table name: #{klass.table_name}\n#\n"

  max_size = klass.column_names.collect{|name| name.size}.max + 1
  klass.columns.each do |col|
    attrs = []
    attrs << "default(#{quote(col.default)})" unless col.default.nil?
    attrs << "not null" unless col.null
    attrs << "primary key" if col.name == klass.primary_key

    col_type = col.type.to_s
    if col_type == "decimal"
      col_type << "(#{col.precision}, #{col.scale})"
    else
      col_type << "(#{col.limit})" if col.limit
    end

    #...        
end