This question is in regards to relational databases and MySQL. Please provide ex

Question

This question is in regards to relational databases and MySQL. Please provide explanatory answers.

Many thanks in advance.

Assume that a trigger, T, is created that inserts into relation R whenever a tuple is inserted into relation S. Further assume that a view, V, is created, separate from the trigger, that selects all the tuples from relation S. Answer the following questions. a. Which relation is stored on disk, R or V? b. What happens to R if a tuple is deleted from S? c. What happens to V if a tuple is deleted from S?

Explanation / Answer

a) View is the result set of a stored query on the data that behaves as database but doesn't have physical address. So R is the one stored on disk.

b)

R and S both are different different database so if something is getting deleted from S data will be available in R.

c)

If tupple deleted from S than view of S that is V will be INVALID.

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