①數(shù)據(jù)定義;數(shù)據(jù)操縱; ②數(shù)據(jù)庫運行管理;數(shù)據(jù)組織、存儲和管理; ③數(shù)據(jù)的建立和維護;數(shù)據(jù)通信接口。
①數(shù)據(jù)結構; ②數(shù)據(jù)操作; ③數(shù)據(jù)約束條件。