Class 2 | Week 11 | DAT601

 Today's lesson theme pertains to referential integrity which Todd has in part assumed we already are familiar with from our previous level 5 DAT course although he has left resources within the course content for those who need a refresher on this content. CASCADE on delete is mentioned as a form of aiding in referential integrity if a primary key is set to cascade on delete it will remove all rows from other tables that also include this key as a primary key.

Constraint checks are our next topic and these are used to constrain an attribute so that an entry into its field must be between or of a specific value or set of values.

After viewing a very insightful video on constrains checks we have been assigned the rest of the class has been assigned to assignment work.


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