Q155 Which four statements are true regarding primary and foreign key constraints and the effect they can have on table data?
- A) A table can have only one primary key but multiple foreign keys
- B) A table can have only one primary key and one foreign key
- C) The foreign key columns and parent table primary key columns must have the same names
- D) It is possible for child rows that have a foreign key to remain in the child table at the time the parent row is deleted
- E) It is possible for child rows that have a foreign key to be deleted automatically from the child table at the time the parent row is deleted.
- F) Only the primary key can be defined at the column and table level
- G) Primary key and foreign key constraints can be defined at both the column and table level
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