Basic SQL Select Queries

Qn 1. This first question in SQL helped me to recollect the basics I learnt. The solution came to me almost instantly requiring not much thought. The question wants the rows in column CITY that has ID 1661. SELECT * FROM city WHERE id = 1661 ; Qn 2. This was also pretty intuitive knowing the very basics that were brushed up in class. select * from city where countrycode = 'USA' and population > 100000 ; Qn 3. Another easy query returning one column using where clause. select * from city where countrycode = 'JPN' ; Qn 4. This was a little challenging at first. I couldn't remember count so it threw me off a bit. Then i looked at the problem logically and not just trying to remember the syntax, thinking "How will i get the number of rows in city column?" That's when it hit me and I got the word count . With that it was easy to solve. select count ( city ) - count ( distinct city ) from station ; Qn 5. Another simple where clause query which was successful in the first attempt. select name