1 files changed, 53 insertions, 13 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 6704843c07..d4b9e301bc 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -67,6 +67,7 @@ module ActiveRecord
       include QueryCache
       include ActiveSupport::Callbacks
       include ColumnDumper
+      include Savepoints
 
       SIMPLE_INT = /\A\d+\z/
 
@@ -104,8 +105,15 @@ module ActiveRecord
         @config              = config
         @pool                = nil
         @schema_cache        = SchemaCache.new self
-        @visitor             = nil
-        @prepared_statements = false
+        @quoted_column_names, @quoted_table_names = {}, {}
+        @visitor             = arel_visitor
+
+        if self.class.type_cast_config_to_boolean(config.fetch(:prepared_statements) { true })
+          @prepared_statements = true
+          @visitor.extend(DetermineIfPreparableVisitor)
+        else
+          @prepared_statements = false
+        end
       end
 
       class Version
@@ -141,8 +149,12 @@ module ActiveRecord
         end
       end
 
+      def arel_visitor # :nodoc:
+        Arel::Visitors::ToSql.new(self)
+      end
+
       def valid_type?(type)
-        true
+        false
       end
 
       def schema_creation
@@ -236,6 +248,11 @@ module ActiveRecord
         false
       end
 
+      # Does this adapter support expression indices?
+      def supports_expression_index?
+        false
+      end
+
       # Does this adapter support explain?
       def supports_explain?
         false
@@ -277,6 +294,21 @@ module ActiveRecord
         false
       end
 
+      # Does this adapter support metadata comments on database objects (tables, columns, indexes)?
+      def supports_comments?
+        false
+      end
+
+      # Can comments for tables, columns, and indexes be specified in create/alter table statements?
+      def supports_comments_in_create?
+        false
+      end
+
+      # Does this adapter support multi-value insert?
+      def supports_multi_insert?
+        true
+      end
+
       # This is meant to be implemented by the adapters that support extensions
       def disable_extension(name)
       end
@@ -378,12 +410,6 @@ module ActiveRecord
         @connection
       end
 
-      def create_savepoint(name = nil)
-      end
-
-      def release_savepoint(name = nil)
-      end
-
       def case_sensitive_comparison(table, attribute, column, value)
         if value.nil?
           table[attribute].eq(value)
@@ -405,10 +431,6 @@ module ActiveRecord
       end
       private :can_perform_case_insensitive_comparison_for?
 
-      def current_savepoint_name
-        current_transaction.savepoint_name
-      end
-
       # Check the connection back in to the connection pool
       def close
         pool.checkin self
@@ -432,6 +454,24 @@ module ActiveRecord
         visitor.accept(node, collector).value
       end
 
+      def combine_bind_parameters(
+        from_clause: [],
+        join_clause: [],
+        where_clause: [],
+        having_clause: [],
+        limit: nil,
+        offset: nil
+      ) # :nodoc:
+        result = from_clause + join_clause + where_clause + having_clause
+        if limit
+          result << limit
+        end
+        if offset
+          result << offset
+        end
+        result
+      end
+
       protected
 
       def initialize_type_map(m) # :nodoc: