Q During peak periods, Temporary Employment Corporation (TEC) places temporary workers in companies. Create a complete ERD to support the business needs described below. Use appropriate primary keys and attributes.
• TEC has a file of candidates who are willing to work. Any candidate who has worked before has a specific job history. (Naturally, no job history exists if the candidate has never worked.) Each time the candidate works, one additional job history record is created.
• Each candidate has earned several qualifications. Each qualification may be earned by more than one candidate. (For example, more than one candidate may have earned a Bachelor of Business Administration degree or a Microsoft Network Certification, and clearly a candidate may have earned both a BBA and a Microsoft Network Certification.)
• TEC offers courses to help candidates improve their qualifications.
• Every course develops one specific qualification; however, TEC does not offer a course for every qualification. Some qualifications are developed through multiple courses.
• Some courses cover advanced topics that require specific qualifications as prerequisites. Some courses cover basic topics that do not require any prerequisite qualifications. A course can have several prerequisites. A qualification can be a prerequisite for more than one course.
• Courses are taught during training sessions. A training session is the presentation of a single course. Overtime, TEC will offer many training sessions for each course; however, new courses may not have any training sessions scheduled right away.
• Candidates can pay a fee to attend a training session. A training session can accommodate several candidates, although new training sessions will not have any candidates registered at first.
• TEC also has a list of companies that request temporaries. Each time a company requests a temporary employee, TEC makes an entry in the Openings folder. That folder contains an opening number, a company name, required qualifications, a starting date, an anticipated ending date, and hourly pay.
• Each opening requires only one specific or main qualification.
• When a candidate matches the qualification, the job is assigned , and an entry is made in the Placement Record folder. The folder contains such information as an opening number, a candidate number, and the total hours worked. In addition, an entry is made in the job history for the candidate.
• An opening can be filled by many candidates, and a candidate can fill many openings.
• TEC uses special codes to describe a candidate's qualifications for an opening.
Q2B: Convert your ERD to a relational model.