Bump required PostgreSQL version to 10.0

Rails main currently claims support for PostgreSQL 9.3+.
However, to ensure forward compatibility with PostgreSQL 18 and future releases, we need to establish a more sustainable baseline.

* Changes in this commit:
- Bump minimum required PostgreSQL version from 9.3 to 10.0
- Deprecate `supports_pgcrypto_uuid?` (no longer needed since PostgreSQL 10+ includes pgcrypto by default)

* Reasons for choosing PostgreSQL 10.0 baseline:
- The pg gem v1.6 raises its minimum required PostgreSQL version to 10 via ged/ruby-pg#606
- PostgreSQL 9.3 reached end-of-life in November 2018, and PostgreSQL 9.6 reached end-of-life in November 2021
- While Ruby on Rails has not historically dropped database support solely based on EOL status,
PostgreSQL 9.3 (released in 2013) is now over a decade old and maintaining compatibility becomes increasingly challenging

Discussed at https://discuss.rubyonrails.org/t/proposal-bump-the-minimum-supported-postgresql-version-from-9-3-to-10/89422

Author: yahonda

activerecord/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Bump the minimum PostgreSQL version to 10.0.
+
+    *Yasuo Honda*
+
 *   Fix PostgreSQL schema dumping to handle schema-qualified table names in foreign_key references that span different schemas.
 
         # before

activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb

@@ -503,11 +503,7 @@ def select_max_column_value_sql(table, column)
 
             def select_min_column_value_sql(sequence)
               quoted_sequence = @adapter.quote_table_name(sequence)
-              if @adapter.database_version >= 10_00_00
-                "SELECT seqmin FROM pg_sequence WHERE seqrelid = #{@adapter.quote(quoted_sequence)}::regclass"
-              else
-                "SELECT min_value FROM #{quoted_sequence}"
-              end
+              "SELECT seqmin FROM pg_sequence WHERE seqrelid = #{@adapter.quote(quoted_sequence)}::regclass"
             end
 
             def reset_sequence_sql(sequence, max_value, min_value)

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -284,7 +284,7 @@ def supports_insert_returning?
       end
 
       def supports_insert_on_conflict?
-        database_version >= 9_05_00 # >= 9.5
+        true
       end
       alias supports_insert_on_duplicate_skip? supports_insert_on_conflict?
       alias supports_insert_on_duplicate_update? supports_insert_on_conflict?
@@ -295,15 +295,15 @@ def supports_virtual_columns?
       end
 
       def supports_identity_columns? # :nodoc:
-        database_version >= 10_00_00 # >= 10.0
+        true
       end
 
       def supports_nulls_not_distinct?
         database_version >= 15_00_00 # >= 15.0
       end
 
       def supports_native_partitioning? # :nodoc:
-        database_version >= 10_00_00 # >= 10.0
+        true
       end
 
       if PG::Connection.method_defined?(:close_prepared) # pg 1.6.0 & libpq 17
@@ -471,8 +471,9 @@ def supports_foreign_tables?
       end
 
       def supports_pgcrypto_uuid?
-        database_version >= 9_04_00 # >= 9.4
+        true
       end
+      deprecate :supports_pgcrypto_uuid?, deprecator: ActiveRecord.deprecator
 
       def supports_optimizer_hints?
         unless defined?(@has_pg_hint_plan)
@@ -706,8 +707,8 @@ def build_insert_sql(insert) # :nodoc:
       end
 
       def check_version # :nodoc:
-        if database_version < 9_03_00 # < 9.3
-          raise "Your version of PostgreSQL (#{database_version}) is too old. Active Record supports PostgreSQL >= 9.3."
+        if database_version < 10_00_00 # < 10.0
+          raise "Your version of PostgreSQL (#{database_version}) is too old. Active Record supports PostgreSQL >= 10.0."
         end
       end
 

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

@@ -232,6 +232,12 @@ def test_release_non_existent_advisory_lock
       end
     end
 
+    def test_supports_supports_pgcrypto_uuid_is_deprecated
+      assert_deprecated(ActiveRecord.deprecator) do
+        @connection.supports_pgcrypto_uuid?
+      end
+    end
+
     private
       def cause_server_side_disconnect
         unless @connection.instance_variable_get(:@raw_connection).transaction_status == ::PG::PQTRANS_INTRANS

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

@@ -254,9 +254,6 @@ class PostgreSQLGeometricLineTest < ActiveRecord::PostgreSQLTestCase
   class PostgresqlLine < ActiveRecord::Base; end
 
   setup do
-    unless ActiveRecord::Base.lease_connection.database_version >= 90400
-      skip("line type is not fully implemented")
-    end
     @connection = ActiveRecord::Base.lease_connection
     @connection.create_table("postgresql_lines") do |t|
       t.line :a_line

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

@@ -11,14 +11,6 @@ def connection
   def drop_table(name)
     connection.drop_table name, if_exists: true
   end
-
-  def uuid_function
-    connection.supports_pgcrypto_uuid? ? "gen_random_uuid()" : "uuid_generate_v4()"
-  end
-
-  def uuid_default
-    connection.supports_pgcrypto_uuid? ? {} : { default: uuid_function }
-  end
 end
 
 class PostgresqlUUIDTest < ActiveRecord::PostgreSQLTestCase
@@ -31,7 +23,7 @@ class UUIDType < ActiveRecord::Base
 
   setup do
     enable_extension!("uuid-ossp", connection)
-    enable_extension!("pgcrypto",  connection) if connection.supports_pgcrypto_uuid?
+    enable_extension!("pgcrypto",  connection)
 
     connection.create_table "uuid_data_type" do |t|
       t.uuid "guid"
@@ -43,14 +35,11 @@ class UUIDType < ActiveRecord::Base
     drop_table "uuid_data_type"
   end
 
-  if ActiveRecord::Base.lease_connection.respond_to?(:supports_pgcrypto_uuid?) &&
-      ActiveRecord::Base.lease_connection.supports_pgcrypto_uuid?
-    def test_uuid_column_default
-      connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "gen_random_uuid()"
-      UUIDType.reset_column_information
-      column = UUIDType.columns_hash["thingy"]
-      assert_equal "gen_random_uuid()", column.default_function
-    end
+  def test_uuid_column_default
+    connection.add_column :uuid_data_type, :thingy, :uuid, null: false, default: "gen_random_uuid()"
+    UUIDType.reset_column_information
+    column = UUIDType.columns_hash["thingy"]
+    assert_equal "gen_random_uuid()", column.default_function
   end
 
   def test_change_column_default
@@ -228,7 +217,7 @@ class UUID < ActiveRecord::Base
     # to test dumping tables which columns have defaults with custom functions
     connection.execute <<~SQL
       CREATE OR REPLACE FUNCTION my_uuid_generator() RETURNS uuid
-      AS $$ SELECT * FROM #{uuid_function} $$
+      AS $$ SELECT * FROM gen_random_uuid() $$
       LANGUAGE SQL VOLATILE;
     SQL
 
@@ -238,7 +227,7 @@ class UUID < ActiveRecord::Base
       t.uuid "other_uuid_2", default: "my_uuid_generator()"
     end
 
-    connection.create_table("pg_uuids_3", id: :uuid, **uuid_default) do |t|
+    connection.create_table("pg_uuids_3", id: :uuid) do |t|
       t.string "name"
     end
   end
@@ -286,11 +275,7 @@ def test_schema_dumper_for_uuid_primary_key_with_custom_default
 
   def test_schema_dumper_for_uuid_primary_key_default
     schema = dump_table_schema "pg_uuids_3"
-    if connection.supports_pgcrypto_uuid?
-      assert_match(/\bcreate_table "pg_uuids_3", id: :uuid, default: -> { "gen_random_uuid\(\)" }/, schema)
-    else
-      assert_match(/\bcreate_table "pg_uuids_3", id: :uuid, default: -> { "uuid_generate_v4\(\)" }/, schema)
-    end
+    assert_match(/\bcreate_table "pg_uuids_3", id: :uuid, default: -> { "gen_random_uuid\(\)" }/, schema)
   end
 
   def test_schema_dumper_for_uuid_primary_key_default_in_legacy_migration
@@ -384,10 +369,10 @@ class UuidComment < ActiveRecord::Base
 
   setup do
     connection.transaction do
-      connection.create_table("pg_uuid_posts", id: :uuid, **uuid_default) do |t|
+      connection.create_table("pg_uuid_posts", id: :uuid) do |t|
         t.string "title"
       end
-      connection.create_table("pg_uuid_comments", id: :uuid, **uuid_default) do |t|
+      connection.create_table("pg_uuid_comments", id: :uuid) do |t|
         t.references :uuid_post, type: :uuid
         t.string "content"
       end
@@ -443,14 +428,14 @@ class UuidComment < ActiveRecord::Base
 
   setup do
     connection.transaction do
-      connection.create_table("pg_uuid_forums", id: :uuid, **uuid_default) do |t|
+      connection.create_table("pg_uuid_forums", id: :uuid) do |t|
         t.string "name"
       end
-      connection.create_table("pg_uuid_posts", id: :uuid, **uuid_default) do |t|
+      connection.create_table("pg_uuid_posts", id: :uuid) do |t|
         t.references :uuid_forum, type: :uuid
         t.string "title"
       end
-      connection.create_table("pg_uuid_comments", id: :uuid, **uuid_default) do |t|
+      connection.create_table("pg_uuid_comments", id: :uuid) do |t|
         t.references :uuid_post, type: :uuid
         t.string "content"
       end

activerecord/test/schema/postgresql_specific_schema.rb

@@ -2,11 +2,9 @@
 
 ActiveRecord::Schema.define do
   ActiveRecord::TestCase.enable_extension!("uuid-ossp", connection)
-  ActiveRecord::TestCase.enable_extension!("pgcrypto",  connection) if supports_pgcrypto_uuid?
+  ActiveRecord::TestCase.enable_extension!("pgcrypto",  connection)
 
-  uuid_default = supports_pgcrypto_uuid? ? {} : { default: "uuid_generate_v4()" }
-
-  create_table :chat_messages, id: :uuid, force: true, **uuid_default do |t|
+  create_table :chat_messages, id: :uuid, force: true do |t|
     t.text :content
   end
 
@@ -15,11 +13,11 @@
     t.text :content
   end
 
-  create_table :uuid_parents, id: :uuid, force: true, **uuid_default do |t|
+  create_table :uuid_parents, id: :uuid, force: true do |t|
     t.string :name
   end
 
-  create_table :uuid_children, id: :uuid, force: true, **uuid_default do |t|
+  create_table :uuid_children, id: :uuid, force: true do |t|
     t.string :name
     t.uuid :uuid_parent_id
   end
@@ -139,23 +137,23 @@
   end
 
   create_table :uuid_comments, force: true, id: false do |t|
-    t.uuid :uuid, primary_key: true, **uuid_default
+    t.uuid :uuid, primary_key: true
     t.string :content
   end
 
   create_table :uuid_entries, force: true, id: false do |t|
-    t.uuid :uuid, primary_key: true, **uuid_default
+    t.uuid :uuid, primary_key: true
     t.string :entryable_type, null: false
     t.uuid :entryable_uuid, null: false
   end
 
   create_table :uuid_items, force: true, id: false do |t|
-    t.uuid :uuid, primary_key: true, **uuid_default
+    t.uuid :uuid, primary_key: true
     t.string :title
   end
 
   create_table :uuid_messages, force: true, id: false do |t|
-    t.uuid :uuid, primary_key: true, **uuid_default
+    t.uuid :uuid, primary_key: true
     t.string :subject
   end
 

guides/source/active_record_postgresql.md

@@ -18,7 +18,7 @@ After reading this guide, you will know:
 
 --------------------------------------------------------------------------------
 
-In order to use the PostgreSQL adapter you need to have at least version 9.3
+In order to use the PostgreSQL adapter you need to have at least version 10.0
 installed. Older versions are not supported.
 
 To get started with PostgreSQL have a look at the

guides/source/command_line.md

@@ -181,7 +181,7 @@ The main difference is the content of the `config/database.yml` file. With the
 PostgreSQL option, it looks like this:
 
 ```yaml
-# PostgreSQL. Versions 9.3 and up are supported.
+# PostgreSQL. Versions 10.0 and up are supported.
 #
 # Install the pg driver:
 #   gem install pg

railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml.tt

@@ -1,4 +1,4 @@
-# PostgreSQL. Versions 9.3 and up are supported.
+# PostgreSQL. Versions 10.0 and up are supported.
 #
 # Install the pg driver:
 #   gem install pg