problem1. Draw Entity-Relationship model for the relational schema given in Appendix. Show all the entities, relationships names, relationship, and attributes and also underline the primary key for each and every entity. Use the SELECT SSADM convention to draw entity.
problem2. prepare the SQL code which will create ALL the tables as given in appendix. Your answer must not contain the primary key and foreign key constraint declaration. The data type for each attribute should be as specified in Appendix II. Suppose that the tables will be associated with the dbo schema. The tables should be created on the Primary Filegroup.
problem3. Supposing that all the tables have been created as given in relational schema in Appendix I, prepare SQL code to make the following changes in structure of tables:
(i) Make employee_id the Primary Key of the EMPLOYEES table
(ii) Make department_id and the manager_id the foreign key of the Employee table supposing that the department_id has been declared as the primary key of DEPARTMENTS.
(iii) Add a check constraint in the Job_History table so that the end_date will always be greater than the start_date.
(iv) Add a unique constraint in the Employee table so that each employee will have a unique email address.