require "active_record/explain_registry" module ActiveRecord module Explain # Executes the block with the collect flag enabled. Queries are collected # asynchronously by the subscriber and returned. def collecting_queries_for_explain # :nodoc: ExplainRegistry.collect = true yield ExplainRegistry.queries ensure ExplainRegistry.reset end # Makes the adapter execute EXPLAIN for the tuples of queries and bindings. # Returns a formatted string ready to be logged. def exec_explain(queries) # :nodoc: str = queries.map do |sql, binds| msg = "EXPLAIN for: #{sql}" unless binds.empty? msg << " " msg << binds.map { |attr| render_bind(attr) }.inspect end msg << "\n" msg << connection.explain(sql, binds) end.join("\n") # Overriding inspect to be more human readable, especially in the console. def str.inspect self end str end private def render_bind(attr) value = if attr.type.binary? && attr.value "<#{attr.value_for_database.to_s.bytesize} bytes of binary data>" else connection.type_cast(attr.value_for_database) end [attr.name, value] end end end