Hi, The following is my feedback of your Assignment 2 of CSC3400 and CSC8500. Hope it will be helpful for you to improve your understanding of the key concepts that are assessed in the assignment. Comments are provided for your reference. Please feel free to contact me at [email protected] for any questions you have regarding to the marking. You can also make an appointment to meet me if you think it is necessary. I am more than happy to give your help and clarification for this assignment. Regards! Ji ***************Objectives for this assessment******************************* 1. Assess your skills in using basic SQL expressions, particular the SELCT clause; 2. Assess your skill in using Relational Algebra (RA) and Domain Relational Calculus (DRC). ************Assignment Marks and Feedback******************** Total: ----------------------------- /20 (a)Relational Algebra----------------- /3 Comments: (a) Relational Calculus--------------- /3 Comments: (a) SQL------------------------------- /3 Comments: (b)---------------------------------- /3 Comments: (c)---------------------------------- /4 Comments: (d)---------------------------------- /4 Comments: The following criteria are considered in evaluating the Relational Algebra, Relational Calculus and SQL statements in your answers. 1. Relational Algebra statements (3 marks) 1.1 The correct algebra operations are used including the correct symbols for presentation (1 mark);1.2 The algebra operations are used in the correct sequential order (1 mark); 1.3 The correct conditions/predicates are defined (1 mark). 2. Relational Calculus statements (3 marks) 2.1 The general structure of the statement is correct (i.e., the left part + I + the right part) (0.5 mark); 2.2 The correct left part – the attributes to be returned by the statement are correct (0.5 mark); 2.3 The correct right part which includes the following three parts 2.3.1 The set of tables used is correct (0.5 marks) 2.3.2 The correct conditions/predicates are defined (0.5 mark); 2.3.2 The necessary quantifier and quantified variables are used correctly (1 mark). 3. SQL statements (3 or 4 marks) 3.1 The correct SQL reserved words and structure are used (1 mark); 3.2 The query produces the correct answer (1 mark for Q(a) and Q(b), 2 marks for Q(c) and Q(d)); 3.3 The screen snapshot is attached which is consistent with the output of the SQL answer provided (1 mark). Note: 1. You may produce different possible solutions to the SQL questions, which is fine. We will mainly evaluate the correctness of your queries. 2. Your SQL answers cannot be hardcoded, meaning that your answers should be general enough to deal with other possible data in the test tables used.