You have been hired to design a database system for a land survey company.

In order to visualize the entire database from a conceptual standpoint, you must complete a conceptual design using the ER/EER data model for it based on the following set of requirements:

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The company has technicians.

Each technician is identified by an employeeID. They also have a name, which is composed of a firstname and a lastname, and a salary. Finally, they may have some certifications.

The company has equipment.

Equipment is identified by an equipmentNumber. Each piece of equipment has a type, manufacturer, and year of purchase.

The company has clients.

Clients are identified by a clientID. Clients also have a contact phone number.

All clients are either corporate or personal clients. Corporate clients have a business name. Personal clients have a lastname and social security number (SSN).

The company works with lots (contiguous chunks of land).

Lots are identified by a county and lot number together. Lot numbers might be repeated between different counties, so both county and lotnumber are required to identify a lot. Lots may have an assessed value. Lots have a description.

Lots have associated coordinates.

Each coordinate of a lot is identified with a sequence number starting at zero. Each coordinate has a latitude and longitude. Each coordinate is associated with exactly one lot. By starting at coordinate zero and progressing to coordinate one, coordinate two, etc, and then returning to coordinate zero, you can define the border of the lot.

Lots have an acreage (area) which is calculated from their coordinates. You will not need to calculate acreage for this project.

Technicians assess lots with the help of equipment. Multiple technicians or equipments may be used in assessing lots, but which equipment is used by which technicians in assessing which lots must be preserved.

Every lot is owned by a single client.

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Please hand draw an ER/EER diagram.

Requirements

Based on the above requirements, our diagram must include composite, derived, and multi-valued attributes; ternary relationships and weak entities; and EER generalization.