SQL
Query all columns (attributes) for every row in the CITY table.
SELECT * FROM CITY
Query all attributes of every Japanese city in the CITY table. The COUNTRYCODE for Japan is JPN
SELECT * FROM CITY WHERE COUNTRYCODE="JPN"
Query all columns for all American cities in CITY with populations larger than 100000. The CountryCode for America is USA.
SELECT * FROM CITY WHERE COUNTRYCODE="USA" AND POPULATION>100000
Query all columns for a city in CITY with the ID 1661.
SELECT * FROM CITY WHERE ID=1661
Query a list of CITY and STATE from the STATION table.
SELECT CITY,STATE FROM STATION
Let be the number of CITY entries in STATION, and let be the number of distinct CITY names in STATION; query the value of from STATION. In other words, find the difference between the total number of CITY entries in the table and the number of distinct CITY entries in the table.
SELECT COUNT(CITY) - COUNT(DISTINCT CITY) FROM STATION
Query a list of CITY names from STATION with even ID numbers only. You may print the results in any order, but must exclude duplicates from your answer.
SELECT DISTINCT CITY FROM STATION WHERE ID % 2 = 0
Query the names of all the Japanese cities in the CITY table. The COUNTRYCODE for Japan is JPN.
SELECT NAME FROM CITY WHERE COUNTRYCODE="JPN"
Query the names of all American cities in CITY with populations larger than 120000. The CountryCode for America is USA.
SELECT NAME FROM CITY WHERE COUNTRYCODE="USA" AND POPULATION>120000