use index based substitution for bind parameters

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -105,7 +105,7 @@ def quote_table_name(name)
 
       # Returns a bind substitution value given a +column+ and list of current
       # +binds+
-      def substitute_for(column, binds)
+      def substitute_at(column, index)
         Arel.sql '?'
       end
 

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -511,8 +511,8 @@ def execute(sql, name = nil)
         end
       end
 
-      def substitute_for(column, current_values)
-        Arel.sql("$#{current_values.length + 1}")
+      def substitute_at(column, index)
+        Arel.sql("$#{index + 1}")
       end
 
       def exec_query(sql, name = 'SQL', binds = [])

activerecord/lib/active_record/relation/finder_methods.rb

@@ -320,7 +320,7 @@ def find_one(id)
 
       column = columns_hash[primary_key]
 
-      substitute = connection.substitute_for(column, @bind_values)
+      substitute = connection.substitute_at(column, @bind_values.length)
       relation = where(table[primary_key].eq(substitute))
       relation.bind_values = [[column, id]]
       record = relation.first

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

@@ -44,7 +44,7 @@ def test_successful_reconnection_after_timeout_with_verify
   end
 
   def test_bind_value_substitute
-    bind_param = @connection.substitute_for('foo', [])
+    bind_param = @connection.substitute_at('foo', 0)
     assert_equal Arel.sql('?'), bind_param
   end
 

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

@@ -102,11 +102,11 @@ def test_exec_typecasts_bind_vals
         assert_equal [['1', 'foo']], result.rows
       end
 
-      def test_substitute_for
-        bind = @connection.substitute_for(nil, [])
+      def test_substitute_at
+        bind = @connection.substitute_at(nil, 0)
         assert_equal Arel.sql('$1'), bind
 
-        bind = @connection.substitute_for(nil, [nil])
+        bind = @connection.substitute_at(nil, 1)
         assert_equal Arel.sql('$2'), bind
       end
 

activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb

@@ -80,7 +80,7 @@ def test_encoding
       end
 
       def test_bind_value_substitute
-        bind_param = @conn.substitute_for('foo', [])
+        bind_param = @conn.substitute_at('foo', 0)
         assert_equal Arel.sql('?'), bind_param
       end
 

activerecord/test/cases/bind_parameter_test.rb

@@ -33,7 +33,7 @@ def test_binds_are_logged
       # FIXME: use skip with minitest
       return unless @connection.supports_statement_cache?
 
-      sub   = @connection.substitute_for(@pk, [])
+      sub   = @connection.substitute_at(@pk, 0)
       binds = [[@pk, 1]]
       sql   = "select * from topics where id = #{sub}"