Based on each pair of primary and foreign key above please i

Based on each pair of primary and foreign key above, please indicate which one is the recursive referential integrity constraint and which one is the MUTUAL recursive referential integrity constraint.

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Solution

Sometimes, it is very useful to disable foreign key checks e.g., when you import data from a CSV file into a table. If you don’t disable foreign key checks, you have to load data into a proper order i.e., you have to load data into parent tables first and then child tables, which can be tedious. However, if you disable the foreign key checks, you can load data in any orders.

Another example is that, unless you disable the foreign key checks, you cannot drop a table that is referenced by a foreign key constraint. When you drop a table, any constraints that you defined for the table are also removed.