On 2017/06/05 17:39, Ashutosh Bapat wrote:
On Fri, Jun 2, 2017 at 2:40 PM, Etsuro Fujita
While updating the patch, I noticed the patch rewrites the UPDATE targetList
incorrectly in some cases; rewrite_inherited_tlist I added to
adjust_appendrel_attrs (1) removes all junk items from the targetList and
(2) adds junk items for the child table using rewriteTargetListUD, but it's
wrong to drop all junk items in cases where there are junk items for some
other reasons than rewriteTargetListUD. Consider junk items containing
MULTIEXPR SubLink. One way I came up with to fix this is to change (1) to
only remove junk items with resname; since junk items added by
rewriteTargetListUD should have resname (note: we would need resname to call
ExecFindJunkAttributeInTlist at execution time!) while other junk items
wouldn't have resname (see transformUpdateTargetList), we could correctly
replace junk items added by rewriteTargetListUD for the parent with ones for
the child, by that change. I might be missing something, though. Comments
welcome.
I haven't looked at the patch, but that doesn't look right. In future
some code path other than rewriteTargetListUD() may add junk items
with resname and this fix will remove those junk items as well.
Yeah, I thought that too. I think we could replace junk tlist entries
added by rewriteTargetListUD() more safely, by adding a lot more code,
but I'm not sure it's worth complicating the code at the current stage.
Best regards,
Etsuro Fujita
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