18.104.22.168 define the connections between tables in database
22.214.171.124 create an entity-relationship (ER) model
Entity Relationship Diagrams
ERDs for your project will need to show the relationships between your tables in your database.
Three types of an entity-relationship:
When linking between two tables, it is common for a field in the first table to link to the primary key of another table. In this case, the field in the first table will be called a foreign key.
The school holds competitions among Shanyrak/Teams. For each useful action, Shanirak points are scored. The deputy director keeps a record of all the items in the notebook. Counting and identifying all points takes a long time, and there may be errors. Automate the work.
Define entities for automated system and types of relationships between entities.
1. What is the usage of ERD?
2. How to draw ERD?
3. Explain what does "One-to-Many" mean?
4. Give examples of relationships "One-to-One", "One-to-Many", "Many-to-Many".
5. Name foreign keys on ERD
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