SQL - Constraints

Which command is used for removing a table and all its data from the database:

• Create command

• Drop table command

• Alter table command

• All of the mentioned

Which constraint(s) can be used to make sure that the column is not left empty?

• NOT NULL

• UNIQUE

• PRIMARY KEY

• ALL THE ABOVE

Which of the following is NOT a type of SQL constraint?

• Primary Key
• Foreign Key
• Alternate Key
• Unique
• NOT NULL

______________ constraint prevents NULL values

• UNIQUE

• NOT NULL

• NULL

• FOREIGN KEY

5. ___________ constraint ensures that no two rows have the same value in the specified columns.

• Primary Key

• Unique

• Default

• Check

6. ___________ which helps to uniquely identify a record.

• Primary key Constraint

• Unique Constraint

• Default constraint

• Check constraint

7. _________ helps to set a limit value placed for a field.

• DEFAULT Constraint

• Primary Key Constraint

• Check Constraint

• TABLE CONSTRAINT

A primary key can be NULL in the table? TRUE or FALSE

• TRUE

• FALSE

SELECT * FROM cars WHERE Doors > 3

would return how many records?

• 1

• 2

• 3

• 4

SELECT * FROM Students WHERE Gender="Female" AND Class=2.2

would return how many records?

• 1

• 2

• 3

• 4