Difference between revisions of "Self join Quiz"
From SQLZOO
(Created page with "SELF JOIN quiz <quiz shuffle=none display=simple> {Which of following would show it is possible to get from Craiglockhart to Haymarket |type="()"} - select distinct a.name, b....") |
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SELF JOIN quiz | SELF JOIN quiz | ||
<quiz shuffle=none display=simple> | <quiz shuffle=none display=simple> | ||
| − | { | + | {Select the code that would show it is possible to get from Craiglockhart to Haymarket |
|type="()"} | |type="()"} | ||
- 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 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' | ||
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- 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 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? |
|type="()"} | |type="()"} | ||
- 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' | - 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' | ||
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| − | { | + | {Select the code that shows the services available from Tollcross? |
|type="()"} | |type="()"} | ||
- 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) | ||
Revision as of 10:50, 23 July 2012
SELF JOIN quiz