Re: [HACKERS] Restrict concurrent update/delete with UPDATE of partition key

On Mon, Mar 12, 2018 at 6:33 PM, amul sul <sulamul@gmail.com> wrote:
> On Mon, Mar 12, 2018 at 11:45 AM, amul sul <sulamul@gmail.com> wrote:
>> On Sat, Mar 10, 2018 at 5:25 PM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>>> complete CTID.
>>
>> Sure, will do that.
>
> I did the aforementioned changes in the attached patch, thanks.
>

--- a/src/include/storage/itemptr.h
+++ b/src/include/storage/itemptr.h
@@ -23,7 +23,9 @@
  * This is a pointer to an item within a disk page of a known file
  * (for example, a cross-link from an index to its parent table).
  * blkid tells us which block, posid tells us which entry in the linp
- * (ItemIdData) array we want.
+ * (ItemIdData) array we want.  blkid is marked InvalidBlockNumber when
+ * a tuple is moved to another partition relation due to an update of
+ * the partition key.

I think instead of updating this description in itemptr.h, you should
update it in htup_details.h where we already have a description of
t_ctid.  After this patch, the t_ctid column value in heap_page_items
function will show it as InvalidBlockNumber and in the documentation,
we have given the reference of htup_details.h.   Other than that the
latest version looks good to me.

I have marked this patch as RFC as this is a small change, hope you
can update the patch soon.

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com