activerecord/test/cases/adapters/postgresql/explain_test.rb


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# frozen_string_literal: true

require "cases/helper"
require "models/author"
require "models/post"

class PostgreSQLExplainTest < ActiveRecord::PostgreSQLTestCase
  fixtures :authors

  def test_explain_for_one_query
    explain = Author.where(id: 1).explain
    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\$1 \[\["id", 1\]\]|1)), explain
    assert_match %(QUERY PLAN), explain
  end

  def test_explain_with_eager_loading
    explain = Author.where(id: 1).includes(:posts).explain
    assert_match %(QUERY PLAN), explain
    assert_match %r(EXPLAIN for: SELECT "authors"\.\* FROM "authors" WHERE "authors"\."id" = (?:\$1 \[\["id", 1\]\]|1)), explain
    assert_match %r(EXPLAIN for: SELECT "posts"\.\* FROM "posts" WHERE "posts"\."author_id" = (?:\$1 \[\["author_id", 1\]\]|1)), explain
  end
end