Batch insertion in rails 3

ruby-on-rails ruby ruby-on-rails-3 activerecord rails-postgresql
phoenixwizard picture phoenixwizard · Apr 3, 2013 · Viewed 31.2k times · Source

I want to do a batch insert of few thousand records into the database (POSTGRES in my case) from within my Rails App.

What would be the "Rails way" of doing it? Something which is fast and also correct way of doing it.

I know I can create the SQL query by string concatenation of the attributes but I want a better approach.

Answer

Simone Carletti picture Simone Carletti · Apr 3, 2013

ActiveRecord .create method supports bulk creation. The method emulates the feature if the DB doesn't support it and uses the underlying DB engine if the feature is supported.

Just pass an array of options.

# Create an Array of new objects
User.create([{ :first_name => 'Jamie' }, { :first_name => 'Jeremy' }])

Block is supported and it's the common way for shared attributes.

# Creating an Array of new objects using a block, where the block is executed for each object:
User.create([{ :first_name => 'Jamie' }, { :first_name => 'Jeremy' }]) do |u|
  u.is_admin = false
end

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