The PADS

My solution:

SELECT CONCAT(Name, "(", LEFT(Occupation, 1), ")") 
FROM   OCCUPATIONS 
ORDER  BY Name; 

SELECT CONCAT("There are a total of ", COUNT(Occupation), " ", LCASE(Occupation) 
       , "s.") 
FROM   OCCUPATIONS 
GROUP  BY Occupation 
ORDER  BY COUNT(Occupation), 
          Occupation; 

Type of Triangle

My solution:

SELECT IF(( A + B > C 
            AND ABS(A - B) < C ) 
          AND ( A + C > B 
                AND ABS(A - C) < B ) 
          AND ( B + C > A 
                AND ABS(B - C) < A ), IF (A = B 
                                          AND A = C 
                                          AND B = C, "Equilateral", 
                                      IF(A = B 
                                          OR B = C 
                                          OR A = C, "Isosceles", "Scalene")), 
              "Not A Triangle") 
FROM   TRIANGLES; 

Employee Salaries

My solution:

SELECT name 
FROM   Employee 
WHERE  salary > 2000 
       AND months < 10 
ORDER  BY employee_id; 

Employee Names

My solution:

SELECT name 
FROM   Employee 
ORDER  BY name; 

Higher Than 75 Marks

My solution:

SELECT Name 
FROM   STUDENTS 
WHERE  Marks > 75 
ORDER  BY RIGHT(Name, 3), 
          ID; 

Weather Observation Station 12

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY REGEXP "^[^AEIOU].*[^aeiou]$"; 

Weather Observation Station 5

My solution:

(SELECT CITY, 
        LENGTH(CITY) 
 FROM   STATION 
 GROUP  BY CITY 
 HAVING LENGTH(CITY) <= (SELECT MIN(LENGTH(CITY)) 
                         FROM   STATION) 
 LIMIT  1) 
UNION 
(SELECT CITY, 
        LENGTH(CITY) 
 FROM   STATION 
 GROUP  BY CITY 
 HAVING LENGTH(CITY) >= (SELECT MAX(LENGTH(CITY)) 
                         FROM   STATION) 
 LIMIT  1); 

Weather Observation Station 11

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY REGEXP "^.*[^aeiou]$" 
        OR CITY REGEXP "^[^AEIOU].*$"; 

Weather Observation Station 10

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY REGEXP "^.*[^aeiou]$"; 

Weather Observation Station 9

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY REGEXP "^[^AEIOU].*$"; 

Weather Observation Station 8

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY REGEXP "^(A|E|I|O|U).*(a|e|i|o|u)$"; 

Weather Observation Station 7

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY LIKE "%A" 
        OR CITY LIKE "%E" 
        OR CITY LIKE "%I" 
        OR CITY LIKE "%O" 
        OR CITY LIKE "%U"; 

Weather Observation Station 6

My solution:

SELECT DISTINCT CITY 
FROM   STATION 
WHERE  CITY LIKE "A%" 
        OR CITY LIKE "E%" 
        OR CITY LIKE "I%" 
        OR CITY LIKE "O%" 
        OR CITY LIKE "U%";