?????????????????????????20?????????

????1????????????????????????????? School?? SchoolCourse?? CourceID??

????2?????????????????????????????? StudentCourse????????StudentCourses??

????3?????????????????

????4??????????????ò???????????????????????School????????TblSchool??????SchoolTable????

????5????????е???????????????????????? (???????д洢?????????)

????6????????????ID??Σ?????????????????????????????????????????????????

????7???????????????????????????????????????? ??

????8????? bit ?????????Σ????????????varcha??????????????????????“Is”?????

????9???????????????????????????????????????????

????10?????????????“select *”???????“select [required_column_list]”?????????????

????11?????????????????????ORM????????hibernate??iBatis??ORM?????????????????????????????????

????12??????????????????????????洢?????????????

????13???????????????e?????????????繒??????????

????14???????????????????????????????????????????е?????????????

????15???????????????????????????????????????д??????????????????洢??????????????

????16????????????????????????????????????????????????????????????ν?????????

????17?????????????????????????÷??????????????????????????????CPU?????

????18??Image??blob??β???????????????????У??????????????

????19?????(Normalization)?????????????????????Normalization?????????????????????????Normalization ????????join?????????????????????????????

????20??????????????????????????????????????????????????