28、USER1. EMP has a referential Integrity constraint defined on EMP.DNO that references USER1.DEPT.DNO.
user1 executes these commands:
SQL> UPDATE dept SET 1oc=’UK’ where dno=1;
1 row updated
SQL> UPDATE emp SET sal=1000 whore eno=100;
1 row updated
SQL> ALTER TABLE dept DROP(dno);
What will be the outcome and why?
A) It will fail because a referential Integrity constraint Is defined on USER1. EMP.
B) It will fall because there Is an uncommitted transaction on USER1. EMP.
C) It will fail because there is an uncommitted transaction on USER1. DEPT.
D) It will execute successfully and drop DEPT. DNO.
E) It will execute successfully and drop the DEPT. DNO and EMP. DNO columns.
Answer:A
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