sql functions

Which SQL function is used to find the average value of any column?

• Mean()

• Avg()

• Average()

• Sum()

What will be the output of the query :

Select Substring('mysql application',3,3)

• app

• mysql

• application

• sql

What will be the output of following query:

Select length(trim(' exam '));

• exam

• exam

• 6

• 4

Which of the following are the five built-in functions provided by SQL?

• A. COUNT, SUM, AVG, MAX, MIN

• B. SUM, AVG, MIN, MAX, MULT

• C. SUM, AVG, MULT, DIV, MIN

• D. SUM, AVG, MIN, MAX, NAME

The SQL statement

SELECT ROUND(45.926, -1) FROM DUAL;

• A) is illegal

• B) prints garbage

• C) prints 045.926

• D) prints 50

The string function that returns the index of the first occurrence of substring is _____________

• a) INSERT()

• b) INSTR()

• c) INSTRING()

• d) INFSTR()

Which SQL function is used to count the number of rows in a SQL query?

• COUNT()

• NUMBER()

• SUM()

• COUNT(*)

The MIN() function returns the smallest value of the selected column.

• True
• False

A table T_COUNT has 12 number values as 1, 2, 3, 32, 1, 1, null, 24, 12, null, 32, null. Predict the output of the below query.

SELECT COUNT (*) FROM t_count;

• 12

• 6

• 9

• Throws exception because COUNT function doesn't works with NULL values

In a column named "age", containing values 4, 5, 6, the SQL statement "SELECT SUM(age) FROM students;" will return,

• 3

• 15

• 0

• 1