search inside partitions

Hi to all,

I have a table, from which I can extract partitions which need to be ordered, one after the other. A partition is composed of 2 columns A and B and ordering is done by finding the next value of B in another row of the partition.

Here are the two columns of one of the partitions :

Starting from the first row the goal is to find the same value in previous of following rows, column A or B.

Example : starting from row 1, 15208 returns row 2 15208-15209, 15209 returns row 15209-15210, 15210 returns 15210-2000 and so on. When the next row is find, a third column C is incremented to be used for sorting

results should then be

By the way, switching has to be done to have always previous B -> next A but this is less important as it can be done using tricks like putting a minus sign when required and switching afterwards.

I'm wondering if there is a rather simple way to do that using partition functions or if I should better try do that using C#

Thanks for any idea,

Olivier