A special-purpose language designed for managing data held in a relational database.
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Revising the Select Query I | Query the data for all American cities with populations larger than 100,000. | SQL | Easy |
| Revising the Select Query II | Query the city names for all American cities with populations larger than 120,000. | SQL | Easy |
| Select All | Query all columns for every row in a table. | SQL | Easy |
| Select By ID | Query the details of the city with ID 1661. | SQL | Easy |
| Japanese Cities' Attributes | Query the attributes of all the cities in Japan. | SQL | Easy |
| Japanese Cities' Names | In this challenge, you will query a list of all the Japanese cities' names. | SQL | Easy |
| Weather Observation Station 1 | Write a query to print the CITY and STATE for each attribute in the STATION table. | SQL | Easy |
| Weather Observation Station 3 | Query a list of unique CITY names with even ID numbers. | SQL | Easy |
| Weather Observation Station 4 | Find the number of duplicate CITY names in STATION. | SQL | Easy |
| Weather Observation Station 5 | Write a query to print the shortest and longest length city name along with the length of the city names. | SQL | Easy |
| Weather Observation Station 6 | Query a list of CITY names beginning with vowels (a, e, i, o, u). | SQL | Easy |
| Weather Observation Station 7 | Query the list of CITY names ending with vowels (a, e, i, o, u) from STATION. | SQL | Easy |
| Weather Observation Station 8 | Query CITY names that start AND end with vowels. | SQL | Easy |
| Weather Observation Station 9 | Query an alphabetically ordered list of CITY names not starting with vowels. | SQL | Easy |
| Weather Observation Station 10 | Query a list of CITY names not ending in vowels. | SQL | Easy |
| Weather Observation Station 11 | Query a list of CITY names not starting or ending with vowels. | SQL | Easy |
| Weather Observation Station 12 | Query an alphabetically ordered list of CITY names not starting and ending with vowels. | SQL | Easy |
| Higher Than 75 Marks | Query the names of students scoring higher than 75 Marks. Sort the output by the LAST three characters of each name. | SQL | Easy |
| Employee Names | Print employee names. | SQL | Easy |
| Employee Salaries | Print the names of employees who earn more than $2000 per month and have worked at the company for less than 10 months. | SQL | Easy |