Problem
The kindergarten allows the parents (caretakers) to select daily the menu for lunch. There are over 40 possible items to be included in the lunch menu. For a lunch item we keep a 4 digits code, its name (up to 28 characters), and the number of calories (an integer).
A parent (caretaker) can make for each of his/her children a lunch order everyday. All orders made are stored. If no order is made in a day the last order made will be provided. An order consists of maximum 6 items. Same item cannot be ordered multiple times in the same order. The order does not store the caretaker who made the order.
1) Identify the main entities involved
2) Identify the main relationship involved.
3) Identify the relationship and explain how you obtained it
4) For many to many relationships identify the bridge, and the two other relationships needed.
5) Entity name
6) Entity description (a short paragraph)
7) An attribute table, with one row for each attribute and with the following columns:
a) Attribute name
b) Attribute domain and size, e.g. CHAR(10), INT, VARCHAR(30)
c) Simple/Composite (without explanations)
d) Single/Multi Value (without explanations)
e) Required/Optional (without explanations)
f) Unique/Duplicated (without explanations)
8) The selected primary key and if its (simple/composite/surrogate).
9) Any foreign key specifying the referenced primary key and entity.
Relationship Analysis
1) Relationship name: PARENT_ENTITY relationship name CHILD_ENTITY (the name is a verb or verb phrase 3rd singular)
2) Relationship with explanation
3) Relationship strength with explanation
4) Entities participation in the relationship with explanations
5) Any special cardinality as needed, or state there is no special cardinality.
6) Foreign key used for representation.