SQL Queries -Functions

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

• Mean()

• Avg()

• Average()

• Sum()

Query to delete all record of table without deleting the table:

• DELETE TABLE TABLE_NAME

• DELETE FROM TABLE_NAME

• DROP TABLE TABLE_NAME

• DELETE TABLE FROM TABLE_NAME

What will be the output of the query :

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

• app

• mysql

• application

• sql

What will be the output of the following query:

Select round(59999.99,-2);

• 59999

• 59900

• 60000

• 59990

Which function will be used to remove only the trailing spaces from a string?

• ltrim()

• rtrim()

• trim()

• all

Fill in the blank:

___________________ this clause is used to apply condition on all the rows of table.

• Where

• Having

• Order By

• Sort By

Fill in the blank:

_________________ this clause is used with GROUP BY to filter the group of records.

What will be the output of following query:

Select length(trim(' exam '));

• exam

• exam

• 6

• 4

Difference between ALTER Table command and UPDATE command :

• ALTER is DDL command and is used for modifying the schema of table

• UPDATE is DML command and is

  used for modifying the existing data of table

• Using Alter command any value inside the table can be modified.

• Using Update command columns of a table can be renamed.

Which clause is used when we want to use aggregate functions in conditions?

• Where

• Group By

• Having

• Both 2 and 3