Multiple choice technology databases

Given the following DDL for the PARTS table: CREATE TABLE parts (part_no INT(9) NOT NULL, part_name VARCHAR(24), part_remain INT(9)); All part numbers entered will be different and all rows should be displayed in order of increasing part numbers whenever the table is queried. Which of the following create index statements will meet this criteria and require the least amount of storage for the index object?

  1. CREATE UNIQUE INDEX idx_partno ON parts(part_no)

  2. CREATE UNIQUE INDEX idx_partno ON parts(part_name ASC)

  3. CREATE UNIQUE INDEX idx_partno ON parts(part_name, part_no ASC)

  4. CREATE UNIQUE INDEX idx_partno ON parts(part_no, part_name ASC)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

CREATE UNIQUE INDEX idx_partno ON parts(part_no) is correct because it creates a unique index on part_no (ensuring all part numbers are different) and orders by part_no by default. It uses the least storage by indexing only the required column. Options B, C, and D incorrectly include part_name in the index or order by the wrong column, increasing storage without meeting the requirements.

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