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....") |
Trust words (Talk | contribs) |
||
| (3 intermediate revisions by one user not shown) | |||
| Line 1: | Line 1: | ||
SELF JOIN quiz | SELF JOIN quiz | ||
| + | |||
| + | <div class='schema'></div> | ||
| + | <div class = 'ref_section'> | ||
| + | <table class = 'db_ref'> | ||
| + | <tr><th>'''stops'''</th><th>'''route'''</th></tr> | ||
| + | <tr><td>id</td><td>num</td></tr> | ||
| + | <tr><td>name</td><td>company</td></tr> | ||
| + | <tr><td></td><td>pos</td></tr> | ||
| + | <tr><td></td><td>stop</td></tr> | ||
| + | <tr><td></td><td></td></tr> | ||
| + | </table> | ||
| + | </div> | ||
| + | |||
<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 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? |
|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' | + | - 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 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='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 | ||
| Line 18: | Line 31: | ||
| − | { | + | {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 10:02, 30 September 2012
SELF JOIN quiz
| stops | route |
|---|---|
| id | num |
| name | company |
| pos | |
| stop | |