Entity relationship diagrams, in simple terms are pictorial/graphic depiction of the interactions between the key components in that given system or event. It's a tool in which data is processed to find the ways to setup a relational oriented database. The ER diagram is similar to analyzing a sentence but in as a pictorial breakup. In the ER diagram, the main players or entities are depicted as circle or oval or points, the relationships between the entities are the lines connecting the above shapes, the degree of these relationship are based on the number of entities in each relationship.
In this scenario
Many students, Many sports
One Head Coach to coach all games
Give names and numbers to the different sports and differnt players
The main components are
1.Entity: This is a definable component, person or an object. The entity can be a strong , weak
entity or an associative entity.This is usually by drawn as a rectangle
2. Relationship: This is basically how the entities interaction with each other and depicted as diamonds, can be strong or weak
3.Attribute. This is a key feature that defines the entity depicted as an oval or a circle. It can be simple or a multi-value attribute.
4. Cardinality: It's the numerical representation of the relationships between entities. It could be one to one or one to many
Label them clearly, attributes can be many, so list the most important ones