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Relationship optionality and cardinality

Relationship optionality and cardinality: Relational Databases Essential Training
Relationship optionality and cardinality: Relational Databases Essential Training

Optionality controls whether the database will require related data between a child and parent table. This ensures that the data stored is complete. Cardinality determines how many records relate to each other. Optionality is controlled by the NULL or NOT NULL attribute of a column, and cardinality is controlled by the presence or absence of a UNIQUE constraint.

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Skill Level Intermediate
2h 12m
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Skills covered in this course
Big Data IT

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