I tested the patch. Basically all of my test cases passed. Just a few small
comments:
+ if (subkey->sk_attno > firstchangingattnum) /*
>, not >= */
+ break;
Can we enhance the comment to something like ">, not >= because
firstchangingattnum starting from 1".
+ /*
+ * Compare the last tuple's datum for this row
compare member
+ * (unless we already know that lasttup must
satisfy qual)
+ */
+ if (!lastsatisfied)
+ {
When subkey->sk_attno <= firstchangingattnum, if first is not satisfied, then
last should not be satisfied either, so we can skip check last.
The new status of this patch is: Waiting on Author
