MySQL Database

What is the output of the following query? mysql> SELECT IFNULL(NULLIF(5, 5), 10); A) 5 B) NULL C) 10 D) Error   Correct Answer: C) 10 Explanation: In this query: NULLIF(5, 5) returns NULL because both values are equal. IFNULL(NULL, 10) returns 10 because the first argument is NULL. Hence, the output of the query […]

MySQL Query world_x database Using the MySQL world_x database, list the codes for countries where English is spoken by more than 30% of the population. Answer: List the codes for countries where English is spoken by more than 30% of the population. You need to join the tables Country and CountryLanguage. Sample SQL query is […]

Q) Let’s consider the database table City from the world MySQL database. What are the correct SQL statements to view the table columns and settings? a) DESC City; b) VIEW City; c) DESCRIBE City; d) SHOW City; Choose the correct options. Answer Explanation The options b and d are NOT correct. The statements are not […]

Q) What is the statement to list the available MySQL databases? a) LIST DATABASES; b) SHOW DATABASES; c) SHOW DATABASES: d) SHOW DATABASES \G Choose all the correct options. Explanation Let’s understand why some options are incorrect and the then learn the correct options and reasons for them. Incorrect Options Options a) and c) are […]

What is a Database Table? A Relational Database Management System( RDBMS) organizes and stores information in the form of tables. The Relational model store information about real-world things in a database table. Database Table A table is an ordered collection of one or more columns and an unordered collection of zero or more rows. Each […]