Merge pull request #34742 from kamipo/row_format_dynamic_by_default

MySQL: `ROW_FORMAT=DYNAMIC` create table option by default

3 files changed, 40 insertions, 7 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index a7aff164c5..1aa756cc7e 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,11 @@
+*   MySQL: `ROW_FORMAT=DYNAMIC` create table option by default.
+
+    Since MySQL 5.7.9, the `innodb_default_row_format` option defines the default row
+    format for InnoDB tables. The default setting is `DYNAMIC`.
+    The row format is required for indexing on `varchar(255)` with `utf8mb4` columns.
+
+    *Ryuta Kamizono*
+
 *   Fix join table column quoting with SQLite.
 
     *Gannon McGibbon*
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
index 66db4e4149..47b5c4b9ec 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
@@ -77,6 +77,10 @@ module ActiveRecord
           super
         end
 
+        def create_table(table_name, options: default_row_format, **)
+          super
+        end
+
         def internal_string_options_for_primary_key
           super.tap do |options|
             if !row_format_dynamic_by_default? && CHARSETS_OF_4BYTES_MAXLEN.include?(charset)
@@ -104,6 +108,20 @@ module ActiveRecord
             end
           end
 
+          def default_row_format
+            return if row_format_dynamic_by_default?
+
+            unless defined?(@default_row_format)
+              if query_value("SELECT @@innodb_file_per_table = 1 AND @@innodb_file_format = 'Barracuda'") == 1
+                @default_row_format = "ROW_FORMAT=DYNAMIC"
+              else
+                @default_row_format = nil
+              end
+            end
+
+            @default_row_format
+          end
+
           def schema_creation
             MySQL::SchemaCreation.new(self)
           end
diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index 0d5b43afe5..2d71ee2f15 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -7,6 +7,7 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   include ConnectionHelper
 
   def setup
+    ActiveRecord::Base.connection.send(:default_row_format)
     ActiveRecord::Base.connection.singleton_class.class_eval do
       alias_method :execute_without_stub, :execute
       def execute(sql, name = nil) sql end
@@ -68,18 +69,18 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
     def (ActiveRecord::Base.connection).data_source_exists?(*); false; end
 
     %w(SPATIAL FULLTEXT UNIQUE).each do |type|
-      expected = "CREATE TABLE `people` (#{type} INDEX `index_people_on_last_name`  (`last_name`))"
+      expected = /\ACREATE TABLE `people` \(#{type} INDEX `index_people_on_last_name`  \(`last_name`\)\)/
       actual = ActiveRecord::Base.connection.create_table(:people, id: false) do |t|
         t.index :last_name, type: type
       end
-      assert_equal expected, actual
+      assert_match expected, actual
     end
 
-    expected = "CREATE TABLE `people` ( INDEX `index_people_on_last_name` USING btree (`last_name`(10)))"
+    expected = /\ACREATE TABLE `people` \( INDEX `index_people_on_last_name` USING btree \(`last_name`\(10\)\)\)/
     actual = ActiveRecord::Base.connection.create_table(:people, id: false) do |t|
       t.index :last_name, length: 10, using: :btree
     end
-    assert_equal expected, actual
+    assert_match expected, actual
   end
 
   def test_index_in_bulk_change
@@ -106,7 +107,13 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
   end
 
   def test_create_mysql_database_with_encoding
-    assert_equal "CREATE DATABASE `matt` DEFAULT CHARACTER SET `utf8mb4`", create_database(:matt)
+    if row_format_dynamic_by_default?
+      assert_equal "CREATE DATABASE `matt` DEFAULT CHARACTER SET `utf8mb4`", create_database(:matt)
+    else
+      error = assert_raises(RuntimeError) { create_database(:matt) }
+      expected = "Configure a supported :charset and ensure innodb_large_prefix is enabled to support indexes on varchar(255) string columns."
+      assert_equal expected, error.message
+    end
     assert_equal "CREATE DATABASE `aimonetti` DEFAULT CHARACTER SET `latin1`", create_database(:aimonetti, charset: "latin1")
     assert_equal "CREATE DATABASE `matt_aimonetti` DEFAULT COLLATE `utf8mb4_bin`", create_database(:matt_aimonetti, collation: "utf8mb4_bin")
   end
@@ -159,12 +166,12 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
       [:temp],
       returns: false
     ) do
-      expected = "CREATE TEMPORARY TABLE `temp` ( INDEX `index_temp_on_zip`  (`zip`)) AS SELECT id, name, zip FROM a_really_complicated_query"
+      expected = /\ACREATE TEMPORARY TABLE `temp` \( INDEX `index_temp_on_zip`  \(`zip`\)\)(?: ROW_FORMAT=DYNAMIC)? AS SELECT id, name, zip FROM a_really_complicated_query/
       actual = ActiveRecord::Base.connection.create_table(:temp, temporary: true, as: "SELECT id, name, zip FROM a_really_complicated_query") do |t|
         t.index :zip
       end
 
-      assert_equal expected, actual
+      assert_match expected, actual
     end
   end