Oracle Exam 1Z0-909 Topic 3 Question 50 Discussion

Actual exam question for Oracle's 1Z0-909 exam

Question #: 50
Topic #: 3

[All 1Z0-909 Questions]

Examine the appointments table definition which contains one million rows:

Now, examine this statement which executes successfully:

Which statement will improve query performance?

AALTER TABLE appointments add index IX_4

BALTER TABLE appointments add index IX_1(credit,payment)

CALTER TABLE appointments add index IX_2(attendant_session_id, created_by)

DALTER TABLE appointments add index IX_3(attendant_id, created_by)

Show Suggested Answer

Suggested Answer: A

by Kizzy at Sep 16, 2024, 09:44 AM

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Darrin

2 months ago

Indexing can be a real 'pain in the index' sometimes, amirite? But seriously, I think Option B is the way to go here.

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Abel

2 months ago

This question is making me hungry. I could really go for an appointment at a nice restaurant right about now.

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Francine

18 days ago

D) I think option C will improve query performance.

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Luke

29 days ago

C) ALTER TABLE appointments add index IX_2(attendant_session_id, created_by)

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Shannan

29 days ago

B) That statement won't improve query performance.

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Anika

1 months ago

A) ALTER TABLE appointments add index IX_4(attendant_id, payment, credit)

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Gianna

2 months ago

Option D looks good to me. Indexing on `(attendant_id, created_by)` should help the query find the relevant rows faster.

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Mari

24 days ago

I also believe option D is the most suitable for improving query performance.

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Fernanda

24 days ago

Yes, I agree. Indexing on (attendant_id, created_by) seems like the right move.

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Tashia

1 months ago

I think option D is the best choice. It will improve query performance.

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Aleisha

2 months ago

I'm not sure, but Option B seems like the most straightforward way to index the relevant columns used in the query.

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Britt

2 months ago

Hmm, the table definition has a lot of columns. I think adding an index on `(attendant_id, payment, credit)` would be the best choice to improve query performance.

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Ma

2 months ago

I think option A) is better because it includes all three columns in the index, which would be more efficient.

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Iesha

2 months ago

But what about option B) ALTER TABLE appointments add index IX_1(credit, payment)? Do you think that could also help?

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Catalina

2 months ago

I agree, adding an index on those columns would definitely improve query performance.

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Hillary

2 months ago

I think option A) ALTER TABLE appointments add index IX_4(attendant_id, payment, credit) would be the best choice.

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Tanesha

3 months ago

That's a good point, but I still think option A is more efficient overall.

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Vallie

3 months ago

I disagree, I believe option B is better as it includes the columns in the order they are used in the query.

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Tanesha

3 months ago

I think option A will improve query performance because it includes multiple columns in the index.

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