Ruby & Rails.

Dynamic language and convention-over-configuration web framework. Covers 8 sub-skills.

• Ruby & Rails · 1 of 3

  OOP & Metaprogramming

  Which call returns the list of method names an object can respond to?

  Aobj.routinesBobj.membersCobj.actionsDobj.methods

• Ruby & Rails · 2 of 3

  Core Syntax & Blocks

  What is the Enumerable module in Ruby?

  AA base class that Ruby collections have to inherit fromBA module available on Array and Hash and nowhere elseCA mixin giving collection methods to a class with eachDA gem for working with the lazily evaluated enumerators

• Ruby & Rails · 3 of 3

  ActiveRecord & Migrations

  When inserting many rows, how does Order.insert_all(rows) differ from rows.each { |r| Order.create!(r) }?

  Ainsert_all returns hydrated model objects ready for immediate iterationBinsert_all skips validations and callbacks for one bulk SQL statementCinsert_all wraps each row in its own implicit transaction with rollbackDinsert_all runs validations once per batch and emits per-row callbacks