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diff --git a/activerecord/test/cases/statement_cache_test.rb b/activerecord/test/cases/statement_cache_test.rb
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+++ b/activerecord/test/cases/statement_cache_test.rb
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+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/book"
+require "models/liquid"
+require "models/molecule"
+require "models/electron"
+
+module ActiveRecord
+  class StatementCacheTest < ActiveRecord::TestCase
+    def setup
+      @connection = ActiveRecord::Base.connection
+    end
+
+    def test_statement_cache
+      Book.create(name: "my book")
+      Book.create(name: "my other book")
+
+      cache = StatementCache.create(Book.connection) do |params|
+        Book.where(name: params.bind)
+      end
+
+      b = cache.execute([ "my book" ], Book.connection)
+      assert_equal "my book", b[0].name
+      b = cache.execute([ "my other book" ], Book.connection)
+      assert_equal "my other book", b[0].name
+    end
+
+    def test_statement_cache_id
+      b1 = Book.create(name: "my book")
+      b2 = Book.create(name: "my other book")
+
+      cache = StatementCache.create(Book.connection) do |params|
+        Book.where(id: params.bind)
+      end
+
+      b = cache.execute([ b1.id ], Book.connection)
+      assert_equal b1.name, b[0].name
+      b = cache.execute([ b2.id ], Book.connection)
+      assert_equal b2.name, b[0].name
+    end
+
+    def test_find_or_create_by
+      Book.create(name: "my book")
+
+      a = Book.find_or_create_by(name: "my book")
+      b = Book.find_or_create_by(name: "my other book")
+
+      assert_equal("my book", a.name)
+      assert_equal("my other book", b.name)
+    end
+
+    def test_statement_cache_with_simple_statement
+      cache = ActiveRecord::StatementCache.create(Book.connection) do |params|
+        Book.where(name: "my book").where("author_id > 3")
+      end
+
+      Book.create(name: "my book", author_id: 4)
+
+      books = cache.execute([], Book.connection)
+      assert_equal "my book", books[0].name
+    end
+
+    def test_statement_cache_with_complex_statement
+      cache = ActiveRecord::StatementCache.create(Book.connection) do |params|
+        Liquid.joins(molecules: :electrons).where("molecules.name" => "dioxane", "electrons.name" => "lepton")
+      end
+
+      salty = Liquid.create(name: "salty")
+      molecule = salty.molecules.create(name: "dioxane")
+      molecule.electrons.create(name: "lepton")
+
+      liquids = cache.execute([], Book.connection)
+      assert_equal "salty", liquids[0].name
+    end
+
+    def test_statement_cache_values_differ
+      cache = ActiveRecord::StatementCache.create(Book.connection) do |params|
+        Book.where(name: "my book")
+      end
+
+      3.times do
+        Book.create(name: "my book")
+      end
+
+      first_books = cache.execute([], Book.connection)
+
+      3.times do
+        Book.create(name: "my book")
+      end
+
+      additional_books = cache.execute([], Book.connection)
+      assert first_books != additional_books
+    end
+
+    def test_unprepared_statements_dont_share_a_cache_with_prepared_statements
+      Book.create(name: "my book")
+      Book.create(name: "my other book")
+
+      book = Book.find_by(name: "my book")
+      other_book = Book.connection.unprepared_statement do
+        Book.find_by(name: "my other book")
+      end
+
+      assert_not_equal book, other_book
+    end
+
+    def test_find_by_does_not_use_statement_cache_if_table_name_is_changed
+      book = Book.create(name: "my book")
+
+      Book.find_by(name: book.name) # warming the statement cache.
+
+      # changing the table name should change the query that is not cached.
+      Book.table_name = :birds
+      assert_nil Book.find_by(name: book.name)
+    ensure
+      Book.table_name = :books
+    end
+
+    def test_find_does_not_use_statement_cache_if_table_name_is_changed
+      book = Book.create(name: "my book")
+
+      Book.find(book.id) # warming the statement cache.
+
+      # changing the table name should change the query that is not cached.
+      Book.table_name = :birds
+      assert_raise ActiveRecord::RecordNotFound do
+        Book.find(book.id)
+      end
+    ensure
+      Book.table_name = :books
+    end
+  end
+end