Re: UPDATE of partition key

On 18 September 2017 at 20:45, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> Please find few more comments.
>
> + * in which they appear in the PartitionDesc. Also, extract the
> + * partition key columns of the root partitioned table. Those of the
> + * child partitions would be collected during recursive expansion.
> */
> + pull_child_partition_columns(&all_part_cols, oldrelation, oldrelation);
> expand_partitioned_rtentry(root, rte, rti, oldrelation, oldrc,
> lockmode, &root->append_rel_list,
> + &all_part_cols,
>
> pcinfo->all_part_cols is only used in case of update, I think we can
> call pull_child_partition_columns
> only if rte has updateCols?
>
> @@ -2029,6 +2034,7 @@ typedef struct PartitionedChildRelInfo
>
> Index parent_relid;
> List *child_rels;
> + Bitmapset *all_part_cols;
> } PartitionedChildRelInfo;
>
> I might be missing something, but do we really need to store
> all_part_cols inside the
> PartitionedChildRelInfo, can't we call pull_child_partition_columns
> directly inside
> inheritance_planner whenever we realize that RTE has some updateCols
> and we want to
> check the overlap?

One thing we will have to do extra is : Open and close the
partitioned rels again. The idea was that we collect the bitmap
*while* we are already expanding through the tree and the rel is open.
Will check if this is feasible.

>
> +extern void partition_walker_init(PartitionWalker *walker, Relation rel);
> +extern Relation partition_walker_next(PartitionWalker *walker,
> + Relation *parent);
> +
>
> I don't see these functions are used anywhere?
>
> +typedef struct PartitionWalker
> +{
> + List *rels_list;
> + ListCell *cur_cell;
> +} PartitionWalker;
> +
>
> Same as above

Yes, this was left out from the earlier implementation. Will have this
removed in the next updated patch.

--
Thanks,
-Amit Khandekar
EnterpriseDB Corporation
The Postgres Database Company