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POHow can I do this in SQL? I need to find possible permutations of a small table of data
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copied!<p>I have this small table of data.</p> <pre><code> Dir LinkL LinkH East 19 27 East 27 29 East 29 31 West 46 49 West 49 51 West 51 61 </code></pre> <p>These represent possible trips. How can I query this? For instance if you started at station 19, you could go from 19->27, 19->29, and 19->31. Three possible "trips" But starting from 27, you only have Two possible "trips", 27->29 & 27->31, lastly starting from 29 gives only one possible trip 29->31. Thats going East, with the same scenario going West you could have 3 possible "trips" starting from station 46, 46->49, 46->51, & 46->61, and so on... Making 12 trip records from the 6 inputs. How do I write a query for something like that? I started with something like this</p> <p><code>SELECT t1.Dir, t1.LinkL FROM tblA t1 INNER JOIN tblA t2 ON t1.Dir = t2.Dir AND t2.LinkL > t1.LinkL</code></p> <p>, but my Sql skills are somewhat limited. </p> <p>The desired output would be something like this</p> <pre><code>East 19 27 East 19 29 East 19 31 East 27 29 East 27 31 East 29 31 West 46 49 West 46 51 West 46 61 West 49 51 West 49 61 West 51 61 </code></pre> <p>Making for 12 possible "trips" Is there anyone out there that can point me in the right direction? I don't mind two separate queries and union the results together. In case the direction makes it more difficult. I'm also trying to avoid the dreaded cursor. </p> <p>Thanks for any help. </p> <p>Cheers,<br> ~ck</p>

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