![]() SET DEFAULT: Although some other database systems allow you to set a column to a default value in case of a reference deletion or update, MySQL does not actually allow this action and will not let you define tables using this option.So if we delete a customer from the customers table, the customer column in the orders table will be set to NULL. SET NULL: This option tells MySQL to set the referencing columns to NULL when the referenced records are removed.The system will reject the update or deletion request. ![]()
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