Explore topic-wise MCQs in Structured Query Language (SQL).

This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Structured Query Language (SQL) knowledge and support exam preparation. Choose a topic below to get started.

1.

The optimizer_prune_level is set by default.

A. True
B. False
Answer» B. False
2.

Which system variable tells how far into the rest of each incomplete plan the optimizer should look to evaluate whether it should be expanded further?

A. optimizer_prune_level
B. optimizer_search_depth
C. optimizer_search
D. optimizer_prune
Answer» C. optimizer_search
3.

Which system variable tells the optimizer to skip certain plans based on estimates of the number of rows accessed for each table?

A. optimizer_prune_level
B. optimizer_search_depth
C. optimizer_search
D. optimizer_prune
Answer» B. optimizer_search_depth
4.

What are the results of the following SQL commands if col is an integer column?

A. same
B. different
C. 1 is an error
D. 2 is an errorView Answer
Answer» B. different
5.

Which of the following WHERE clauses are faster?

A. 1
B. 2
C. same speed
D. dependent on operating systemView Answer
Answer» C. same speed
6.

WHICH_SYSTEM_VARIABLE_TELLS_THE_OPTIMIZER_TO_SKIP_CERTAIN_PLANS_BASED_ON_ESTIMATES_OF_THE_NUMBER_OF_ROWS_ACCESSED_FOR_EACH_TABLE??$

A. optimizer_prune_level
B. optimizer_search_depth
C. optimizer_search
D. optimizer_prune
Answer» B. optimizer_search_depth
7.

sam?

A. different
B. 1 is an error
C. 2 is an error
Answer» C. 2 is an error
8.

Which of these comparisons is slowest?

A. INT/INT
B. INT/BIGINT
C. BIGINT/BIGINT
D. All are of same speed
Answer» C. BIGINT/BIGINT
9.

Which statement is used to force the optimizer to use tables in a particular order?

A. FORCE INDEX
B. USE INDEX
C. IGNORE INDEX
D. STRAIGHT_JOIN
Answer» E.
10.

Which statement is used to verify optimizer operation?

A. ANALYZE
B. VERIFY
C. EXPLAIN
D. SHOW
Answer» D. SHOW
11.

To perform analysis of key values by the server, the statement used is __________

A. ANALYZE KEYS
B. ANALYZE TABLE
C. PERFORM ANALYSIS
D. PERFORM TABLE ANALYSIS
Answer» C. PERFORM ANALYSIS
12.

To check how MySQL would execute a SELECT query, which statement is used?

A. TELL
B. SHOW
C. DISPLAY
D. EXPLAIN
Answer» E.