text: prepare stm from 'select 1*?*? from db_root';
  execute stm using 2,3;
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using 2,'3';
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using '2',3;
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using '2','3';
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using null,'3';
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using null,null;
  deallocate prepare stm;
  
  prepare stm from 'select 1*?*? from db_root';
  execute stm using 'null',3;
  deallocate prepare stm;
  