rails--rails/activerecord/lib/active_record/explain.rb

39 lines
1.1 KiB
Ruby

require 'active_support/lazy_load_hooks'
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, bind|
[].tap do |msg|
msg << "EXPLAIN for: #{sql}"
unless bind.empty?
bind_msg = bind.map {|col, val| [col.name, val]}.inspect
msg.last << " #{bind_msg}"
end
msg << connection.explain(sql, bind)
end.join("\n")
end.join("\n")
# Overriding inspect to be more human readable, specially in the console.
def str.inspect
self
end
str
end
end
end