The Entity-Relationship (ER) model is a conceptual tool for describing what data a system must store and how the pieces of that data relate to one another, before any decisions are made about tables, columns, or storage. It gives designers a small, standardized vocabulary — entities, attributes, relationships, cardinality, and participation — plus a diagram notation that lets a technical team and a non-technical client look at the same picture and agree on what the database is supposed to represent.
This matters in COP4708 because the ER diagram is the bridge between a written problem description and a working relational schema. If the conceptual model misses an entity, mislabels an attribute, or gets a cardinality backwards, those errors propagate into the logical design and eventually into the database itself. Learning to read, build, and critique ER diagrams is therefore a prerequisite skill for everything that follows in the design process.
As you watch the videos below, pay attention to three things. First, how each presenter decides what becomes an entity versus what becomes an attribute — this judgment call is the heart of conceptual modeling. Second, how attributes are classified and how the key attribute is identified and marked. Third, how relationships are named and how cardinality (1:1, 1:N, M:N) is written on the diagram. Also notice that notation varies: Chen-style notation uses rectangles, ovals, and diamonds, while crow's-foot style packs attributes inside the entity box. Both encode the same ideas, so focus on the underlying concepts rather than memorizing one drawing style.
A compact, worked walkthrough of building an ER model for a database, taking an example scenario and developing it step by step. Based on its title and description, it should move through identifying entities, attaching attributes, and connecting entities with relationships, showing how the model takes shape as decisions are made.
The step-by-step example format mirrors exactly what you will be asked to do — translate a described situation into entities, attributes, and relationships — and its short length makes it a good first or refresher pass over the whole ER vocabulary.
A tutorial on building an entity relationship diagram from scratch, covering the basics of entities, attributes, and cardinalities. As Part 1 of a series from a diagramming software company, it is likely to emphasize clean diagram construction and the conventions used to draw each element correctly.
It directly addresses three of this topic's subtopics — entities, attributes, and cardinality — and comes from a producer whose business is diagram notation, so the drawing conventions shown are consistent and widely used in practice.
A brief focused look at the entity-relationship model using Chen notation, framed as a tool developers use to design databases. The video works through an example in Chen's symbol set, where entities, attributes, and relationships each get their own distinct shape.
Chen notation is the notation most often used in textbook ER coverage and in classification exercises for attribute types, so this short clip fills in the notational conventions that crow's-foot-style tutorials tend to skip.
Together these videos build the conceptual layer of the design process that MO1 asks you to distinguish from logical and physical design. The attribute coverage in the Lucid Software and Chen notation videos supports MO2's classification task, while the explicit treatment of cardinality in the first two videos supports MO3. All three are example-driven constructions of a diagram from a scenario, which is the skill tested in MO4, and seeing two different notation conventions side by side gives you the vocabulary and the attention to detail needed to review and critique a drafted diagram as required by MO5.
These videos were chosen from YouTube on October 2, 2026. Each has captions; the player turns them on. Videos on YouTube can be changed or removed — if one no longer plays, tell your instructor. If a player does not appear, use its Watch on YouTube link.