alarmClocks

My solution:

CREATE PROCEDURE alarmClocks() 
BEGIN 
  DROP TABLE IF EXISTS calendarWeek; 

  CREATE TABLE calendarWeek 
    ( 
       `number` INT 
    ); 

  SET @s = 0; 

  loopLabel: 
LOOP 
    INSERT INTO calendarWeek 
                (`number`) 
    VALUES      (@s); 
    SET @s = @s + 1; 
    IF @s <= 53 THEN 
      ITERATE loopLabel; 
    END IF; 
    LEAVE loopLabel; 
  END LOOP loopLabel; 

  SELECT alarm_date 
  FROM   (SELECT DATE_ADD(input_date, INTERVAL (7 * number) DAY) AS alarm_date 
          FROM   userInput, 
                 calendarWeek) AS t, 
         userInput 
  WHERE  YEAR(alarm_date) = YEAR(input_date); 
END 

netIncome

My solution:

CREATE PROCEDURE 
  netIncome() 
BEGIN 
  SELECT   YEAR(   date)                                                AS year, 
           QUARTER(date)                                                AS quarter, 
           SUM(CONVERT(profit, SIGNED INT) - CONVERT(loss, SIGNED INT)) AS net_profit 
  FROM     accounting 
  GROUP BY year, 
           quarter 
  ORDER BY date; 

END

Note:
profit: BIGINT UNSIGNED and
loss: BIGINT UNSIGNED
need to be converted to SIGNED INT.

pastEvents

My solution:

CREATE PROCEDURE pastEvents() 
BEGIN 
  SELECT name, 
         event_date 
  FROM   Events, 
         (SELECT MAX(DATE(event_date)) AS last_date 
          FROM   Events) AS t 
  WHERE  event_date != t.last_date 
         AND DATEDIFF(t.last_date, event_date) <= 7 
  ORDER  BY event_date DESC; 
END 

dateFormatting

My solution:

CREATE PROCEDURE dateFormatting() 
BEGIN 
  SELECT DATE(date_str) AS date_iso 
  FROM   documents 
  ORDER  BY id; 
END 

importantEvents

My solution:

CREATE PROCEDURE importantEvents() 
BEGIN 
  SELECT * 
  FROM   events 
  ORDER  BY ( DAYOFWEEK(event_date) + 5 ) % 7, 
            participants DESC; 
END