国开】《数据库基础与应用》【形考】形考任务1-4答案 .pdf

国开】《数据库基础与应用》【形考】形 考任务 1-4 答案 The formative assessment of this course consists of two parts: XXX of the learning process 。There are a total of four formative assessment assignments 。each accounting for 15% of the total grade 。as detailed in the paper-based XXX. XXX of the learning process accounts for 40% of the formative assessment grade and is designed and assigned by each branch (it is XXX) 。Each chapter of the main textbook of this course from Chapter 7 to Chapter 11 is XXX 。and each branch can choose as needed. XXX XXX: Order Chapter Form Start Time End Time Weight 1 Chapters 1-3 Formative Assessment Assignment Week 3 End of Week 10 15% 2 Chapters 4-5 Formative Assessment Assignment Week 6 End of Week 15 15% 3 Chapters 6-8 Formative Assessment Assignment Week 9 End of Week 15 15% 4 Chapters 9-11 XXX 10 End of Week 15 15% 5 Daily Activity Learning Records Week 1 End of Week 16 40% Each formative assessment task is scored on a percentage basis 。and the XXX by the corresponding weight 。The sum of the scores is the XXX grade for the course. Formative Assessment Task 1 for Database Fundamentals and ns: 1.In the four stages of computer data processing。the third stage is (database system). 2.The attribute in an entity that can XXX is called (a key). 3.XXX data model belongs to (logical data model). 4.If entity A and entity B have a one-to-many nship 。and entity B and entity C have a many-to-one nship 。then entity A and entity C have a (many-to-many) nship. 5.In the three-level schema of the database architecture 。the global schema is in the (middle) layer. 6.The data schema is not one of the three levels of schema in the database architecture. 7.If the cardinality of the domains D1.D2.and D3 are 2.3.and 4.respectively 。then the number of tuples in D1?D2?D3 is (24). 8.If n R1 has a1 at