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  • V_
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Topic: 1z0-082 topic 1 question 116

Which three statements are true about sequences in a single instance Oracle database? (Choose three.)

A.
Sequences can always have gaps.
B.
Two or more tables cannot have keys generated from the same sequence.
C.
A sequence's unallocated cached values are lost if the instance shuts down.
D.
A sequence can issue duplicate values.
E.
A sequence can only be dropped by a DBA.
F.
A sequence number that was allocated can be rolled back if a transaction fails.

Re: 1z0-082 topic 1 question 116

F-FALSE: When a sequence number is generated, the sequence is incremented, independent of the transaction committing or rolling back.
A-TRUE: If two users concurrently increment the same sequence, then the sequence numbers each user acquires may have gaps, because sequence numbers are being generated by the other user

Re: 1z0-082 topic 1 question 116

I agree ACD
C-TRUE:when an instance abnormally shuts down (for example, when an
instance failure occurs or a SHUTDOWN ABORT statement is issued), sequence numbers that
have been cached but not used are lost.
The CACHE clause preallocates a set of sequence numbers and keeps them in memory so that
sequence numbers can be accessed faster
D-TRUE: If the sequence is cycle it can generate duplicate values.

Re: 1z0-082 topic 1 question 116

https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/CREATE-SEQUENCE.html

  • auwia
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Re: 1z0-082 topic 1 question 116

Agree with A, C and D.

Re: 1z0-082 topic 1 question 116

ACD are correct

Re: 1z0-082 topic 1 question 116

Answer is ACD

Re: 1z0-082 topic 1 question 116

B is wrong -> "Sequence numbers are generated independently of tables, so the same sequence can be used for one or for multiple tables"
https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/CREATE-SEQUENCE.html

Re: 1z0-082 topic 1 question 116

https://www.islever.com/discussions/oracle/view/20160-exam-1z0-071-topic-2-question-27-discussion/