Online Access Free 1Z0-909 Exam Questions

Examine the appointments table definition which contains one million rows:

Now, examine this statement which executes successfully:

Which statement will improve query performance?

• A.ALTER TABLE appointments add index IX_3(attendant_id, created_by)
• B.ALTER TABLE appointments add index IX_4<attendant_id, payment, credit)
• C.ALTER TABLE appointments add index IX_1(credit,payment)
• D.ALTER TABLE appointments add index IX_2(attendant_session_id, created_by)

Which two are true about indexes?

• A.Secondary index access will always be faster than a table scan.
• B.Indexing all of a table's columns improves performance.
• C.Indexes contain rows sorted by key values.
• D.Indexes reduce disk space used.
• E.Indexes are used to enforce unique constraints.

Which two statements are true about AUTO_INCREMENT?

• A.An AUTO_INCREMENT column must be indexed.
• B.The decimal data type supports AUTO_INCREMENT.
• C.A server restart always resets the AUTO_INCREMENT value to largest value in the AUTO_INCREMENT column plus 1.
• D.A table can have multiple AUTO_INCREMENT columns.
• E.AUTO_INCREMENT values allocated to a transaction that is rolled back are not reused.

Examine this statement which executes successfully:
SET @ir := 2;
Which query updates the value of @r to 0?

• A.SELECT STRCMP('Car'/Ca?') >= 0 INTO @r;
• B.SELECT 'Car' REGEXP('Ca?') >= 0 INTO @r;
• C.SELECT 'Car' RLIKE 'Ca?' INTO @r;
• D.SELECT 'Car' LIKE 'Ca?' INTO @r;

Examine this bar graph based on columns from the players table:

Which two statements would generate this bar graph?

• A.SELECT Name, Gender, Sport, CHAR_LENGTH ('# ' GPA*10) AS GPA_Graph FROM players ORDER BY GPA DESC;
• B.SELECT Name, Gender, Sport, REPEAT('# 'Y GPA*10) AS GPA_Graph FROM players ORDER BY GPA DESC;
• C.SELECT Name, Gender, Sport, CONCAT ('# ' GPA*10) AS GPA_Graph FROM players ORDER BY GPA DESC;
• D.SELECT Name, Gender, Sport, RPAD ('# ' GPA*10) AS GPA_Graph FROM players ORDER BY GPA DESC;
• E.SELECT Name, Gender, Sport, LENGTH (GPA*10, '# ') AS GPA_Graph FROM players ORDER BY GPA DESC;