ITC556 Database Systems Assessment: ER Diagram and Assumptions

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ITC556 - DATABASE SYSTEMS ASSESSMENT
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Table of Contents
Assumptions....................................................................................................................................3
ER Diagram.....................................................................................................................................4
References........................................................................................................................................5
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Assumptions
There are few assumptions that are considered while creating the ER diagram and these
assumptions are discussed thoroughly here:
 Total numbers of entities that are created are Seven and are connected and dependent on
each other.
 For every entity, there are different constraints added like primary and foreign keys.
 The table BOOKING_TREATMENT created in order to avoid the many-to-many
relationship between the table appointment and treatment (Dunn,et al., (2017)).
 The table appointment connected with a one-to-one relationship with table recorded_data.
 The primary key is used to uniquely identify any data in entity Client ClientID is the
primary key for every client, Rec_ID and CA_ID in table Recorded_Data making it
composite, T_ID for a therapist, Payment_ID for Payments, CT_CODE for treatment and
CA_ID for appointments. All these are primary keys.
 Another constraint is a foreign key in Booking_treatment table, payment and appointment
tables. All these foreign keys are assigned as primary keys in another table so as a foreign
key they are taking reference from other tables.
 There is a one-to-one relationship among the table recorded_data and the appointment as
for booked appointment only one data can be recorded (Harahap, (2019)).
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ER Diagram
Figure 1 ERD
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References
 Harahap, S. H. (2019). ANALISIS PEMBELAJARAN SISTEM AKUNTANSI
MENGGUNAKAN DRAW. IO SEBAGAI PERANCANGAN DIAGRAM ALIR.
 Dunn, C., & Nel, L. D. (2017). Entity Relationship Diagram Mapping.
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