Merge pull request rails#53692 from byroot/fix-mysql2-prepared-statements

Fix Mysql2Adapter support for prepared statements

Author: byroot

activerecord/lib/active_record/connection_adapters/mysql2/database_statements.rb

@@ -53,14 +53,16 @@ def perform_query(raw_connection, sql, binds, type_casted_binds, prepare:, notif
 
               begin
                 ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
-                  stmt.execute(*type_casted_binds)
+                  result = stmt.execute(*type_casted_binds)
                 end
               rescue ::Mysql2::Error
                 @statements.delete(sql)
                 stmt.close
                 raise
               end
               verified!
+
+              result
             else
               raw_connection.query(sql)
             end

activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb

@@ -68,6 +68,11 @@ def close
     assert_equal false, adapter.prepared_statements
   end
 
+  def test_exec_query_with_prepared_statements
+    result = @conn.exec_query("SELECT 1", "SQL", [], prepare: true)
+    assert_equal [{ "1" => 1 }], result.to_a
+  end
+
   def test_exec_query_nothing_raises_with_no_result_queries
     assert_nothing_raised do
       with_example_table do