Hi!
Thank you for your work on the subject.
During review your patch I didn't understand why are you checking that
the variable is path and not new_path of type T_SamplePath (I
highlighted it)?
Path *
reparameterize_path_by_child(PlannerInfo *root, Path *path,
RelOptInfo *child_rel)
...
switch (nodeTag(path))
{
case T_Path:
new_path = path;
ADJUST_CHILD_ATTRS(new_path->parent->baserestrictinfo);
if (*path*->pathtype == T_SampleScan)
{
Is it a typo and should be new_path?
Besides, it may not be important, but reviewing your code all the time
stumbled on the statement of the comments while reading it (I
highlighted it too). This:
* path_is_reparameterizable_by_child
* Given a path parameterized by the parent of the given child
relation,
* see if it can be translated to be parameterized by the child
relation.
*
* This must return true if *and only if *reparameterize_path_by_child()
* would succeed on this path.
Maybe is it better to rewrite it simplier:
* This must return true *only if *reparameterize_path_by_child()
* would succeed on this path.
And can we add assert in reparameterize_pathlist_by_child function that
pathlist is not a NIL, because according to the comment it needs to be
added there:
Returns NIL to indicate failure, so pathlist had better not be NIL.
--
Regards,
Alena Rybakina
