Question 13 Assume R Integer Column Consider Two Queries Q1 Select R Ra 1 Q2 Select R Exce Q29138840

QUESTION 13 Assume R.a is an integer column. Consider these two queries Q1: select * from R where Ra> 1 Q2: (select * from R) except (select from R where Ra<1) Which of the following statements is NOT correct? If R.a is a primary key, then the two queries always have the same results. C If R.a is a foreign key, then the two queries alwavs have the same results, CIf R.a is nullable, then Q2s results may contain NULLs while Q1s results cannot. Q2s results may have fewer tuples than Q1s results. QUESTION 14 Which of the following is a correct procedure when designing a database? 1. (a) Collect all user requirements, and all facts about the data. (b) Design E-R diagrams. (c) Convert E-R diagrams to relational schema. (d) Apply normalization to modify the schema. (e) Determine what indexes and views to create (a) Collect all user requirements, and all facts about the data. (b) Determine what indexes and views to create based on user query workload in (a) (c) Design E-R diagrams based on (a) and (b) (d) Convert E-R diagrams to relational schema. (e) Apply normalization to modify the schema. (a) Collect all user requirements, and all facts about the data. (b) Determine what indexes and views to create based on user query workload in (a) (c) Apply normalization to come up with a first-cut data schema. (d) Design E-R diagrams based on (c) to refine the schema. (e) Create tables based on the final schema identified in (d) C (a) Collect all user requirements, and all facts about the data. (b) Apply normalization to come up with a first-cut data schema. (c) Design E-R diagrams based on (b) to refine the schema. (d) Create tables based on the final schema identified in (c) (e) Determine what indexes and views to create based on query workload.

QUESTION 13 Assume R.a is an integer column. Consider these two queries Q1: select * from R where Ra> 1 Q2: (select * from R) except (select from R where RaShow transcribed image text

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