From the course: Relational Databases Essential Training

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Cascade changes

Cascade changes

From the course: Relational Databases Essential Training

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Cascade changes

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- [Instructor] When records in a table are modified or deleted, it can have downstream effects on other tables that they're related to. Relational database management systems have features that can cascade changes to affected tables in order to maintain the integrity of a relationship. Let's see how this works by looking at the Vacation Photos database again. This time I'm going to focus on the relationship between the Pictures table and the Locations table. These tables are related in a one-to-many relationship based off of the Location fields. If we were to modify the location number for Paris in the Locations table, say change it from two to five, that would cause problems for the database. Now if we were to try and look up where the Eiffel Tower picture was taken, we wouldn't find the matching record in the Locations table. There would be a disconnect in the data, and the relational integrity of the database would be…

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