Question 4. ER model (30 marks). TXT is a logistics and transport company. You are asked to design a database for scheduling their transport jobs. Requirements for the database are as follows: Each truck has a unique registration No, and is also described by type, and year made Each customer of TXT has a unique ABN and is also described by the name, and contact phone number Delivery jobs are identified by the unique job No, and are also described by "from" and "to" destinations, and estimated distance to travel. Drivers are identified by the unique employee ID, and are also described by first name, last name, address and phone number A customer may book in several delivery jobs and a job is from only one customer. A job must have an "owning" customer A driver can be assigned several delivery jobs but a job has only one driver. Some description about the job is also recorded. Each job has a Status (eg open, complete,etc) and this is maintained in the database A job is assigned only one truck but a truck can be assigned to several jobs. According to the given description, state any assumptions you make and construct an Entity Relationship (ER) diagram for the database. You must represent entities, relationships and their attributes, and al applicable constraints in your ER diagram. Explain any concepts in the description that cannot be expressed in the ER diagram. e Your ER diagram must only use notations from the lecture notes and must not be hand drawn. ER diagrams using other notations will receive zero mark for this question. You can use the ER diagramming tool Dia, which can be downloaded from Canvas (The Tools section) and is also available as an App on mydesktop.rmit.edu.au. When exporting your ER diagram in Dia to a pdf file, you need to first set page setup" to Fit to 1 by 1 ,, so that your pdf diagram scales properly. You can also use any other diagramming tooil. e Some common errors in ER diagrams If the scenario is set in say, a club, you do not need an entity for the club. The arrangement you depict in the ER diagram is the club Entities do not connect to other entities with straight lines. Entities have relationships to/with other entities so there has to be a relationship between connected entities. Every entity must have a primary key The names of all relationships and entities must be unique . There are no foreign keys in ER diagrams. They come about as part of mapping an ER model into a relational schema