Self join Quiz

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SELF JOIN quiz

stopsroute
idnum
namecompany
pos
stop
Select the code that would show it is possible to get from Craiglockhart to Haymarket
SELECT DISTINCT a.name, b.name
  FROM stops a JOIN route z IN a.id=z.stop
  JOIN route y ON y.num = z.num
  JOIN stops b IN y.stop=b.id
 WHERE a.name='Craiglockhart' AND b.name ='Haymarket'
SELECT DISTINCT a.name, b.name
  FROM stops a JOIN route z ON a.id=z.stop
  JOIN route y JOIN stops b ON y.stop=b.id
 WHERE a.name='Craiglockhart' AND b.name ='Haymarket'
SELECT DISTINCT a.name, b.name
  FROM stops a JOIN route z ON a.id=z.stop
  JOIN route y ON y.num = z.num
  JOIN stops b ON y.stop=b.id
 WHERE a.name='Craiglockhart' AND b.name ='Haymarket'
SELECT DISTINCT a.name, b.name FROM stops a
  JOIN route z ON a.id=z.stop
  JOIN route y ON y.num = z.num
  JOIN stops b ON y.stop=b.id
 WHERE a.name='Craiglockhart' AND b.name ='Sighthill'
SELECT DISTINCT a.name, b.name
  FROM stops a JOIN route z ON a.id=z.stop
  JOIN route y ON y.num = z.num
  JOIN stops b ON y.stop=b.id
 WHERE y.name='Craiglockhart' AND z.name ='Haymarket'
Select the code that shows the stops that are on route.num '2A' which can be reached with one bus from Haymarket?
SELECT S2.id, S2.name, R2.company, R2.num
  FROM stops S1, stops S2, route R1, route R2
 WHERE S1.name='Haymarket' AND S1.id=R1.stop
   AND R1.company=R2.company AND R1.num=R2.num
   AND R2.stop=S2.id AND R1.num='2A'
SELECT S2.id, S2.name, R2.company, R2.num
  FROM stops S1, stops S2, route R1, route R2
 WHERE S1.name='Craiglockhart' AND S1.id=R1.stop
   AND R1.company=R2.company AND R1.num=R2.num
   AND R2.stop=S2.id AND R2.num='2A'
SELECT S2.id, S2.name, R2.company, R2.num
  FROM stops S1, stops S2, route R1, route R2
 WHERE S1.name='Haymarket' AND S1.id=R1.stop
   AND R1.company=R2.company AND R1.num=R2.num
   AND R2.stop=S2.id
SELECT S2.id, S2.name, R2.company, R2.num
  FROM stops S1, stops S2, route R1, route R2
 WHERE S1.name='Haymarket' AND S1.id=R1.stop
   AND R1.company=R2.company AND R1.num=R2.num
   AND R2.stop=S2.id AND R2.num='2'
SELECT S2.id, S2.name, R2.company, R2.num
  FROM stops S1, stops S2, route R1, route R2
 WHERE S1.name='Haymarket' AND S1.id=R1.stop
   AND R1.company=R2.company AND R1.num=R2.num
   AND R2.stop=S2.id AND R2.num='2A'
Select the code that shows the services available from Tollcross?
SELECT a.company, a.num, stopa.name, stopb.name
  FROM route a JOIN route b ON (a.company=b.company AND a.num=b.num)
  JOIN stops stopa ON (a.stop=stopa.id)
  JOIN stops stopb ON (b.stop=stopb.id)
SELECT a.company, a.num, stopa.name, stopb.name
  FROM route a JOIN route b ON (a.company=b.company AND a.num=b.num)
  JOIN stops stopa ON (a.stop=stopa.id)
  JOIN stops stopb ON (b.stop=stopb.id)
 WHERE stopa.name='Sighthill'
SELECT a.company, a.num, stopa.name, stopb.name
  FROM route a JOIN route b IN (a.company=b.company AND a.num=b.num)
  JOIN stops stopa IN (a.stop=stopa.id)
  JOIN stops stopb ON (b.stop=stopb.id)
 WHERE stopa.name='Tollcross'
SELECT a.company, a.num, stopa.name, stopb.name
  FROM route a JOIN route b ON (a.company=b.company AND a.num=b.num)
  JOIN stops stopa ON (a.stop=stopa.id)
  JOIN stops stopb ON (b.stop=stopb.id)
 WHERE stopa.name='Tollcross'
SELECT a.company, a.num, stopa.name, stopb.name
  FROM route a JOIN route b ON (a.company=b.company AND a.num=b.num)
  JOIN stops stopa ON (a.stop=stopa.id)
  JOIN stops stopb ON (b.stop=stopb.id)
 WHERE stopz.name='Tollcross'