It seems the way of specifying per-partition definition/constraint, especially for range partitioning, would have a number of interesting alternatives.
By the way, the [USING opclass_name] bit is just a way of telling that a particular key column has user-defined notion of "ordering" in case of range partitioning and "equality" for list partitioning. The opclass would eventually determine which WHERE clauses (looking at operators, operand types) are candidates to help prune partitions. If we use the range_op range_literal::range_type notation to describe partition constraint for each partition, it might not offer much beyond the readability. We are not really going to detect range operators being applied in WHERE conditions to trigger partition pruning, for example. Although I may be missing something...
I don't think it's important that ranges be used internally for partition pruning, though I don't see a reason why they couldn't. I was making the case for range types being used at partition creation/declaration time, because you were proposing new syntax to describe a range of values in text when we already have that in range types. We should eat our own dog food.
But mostly, I wanted to make sure that range partitions could have inclusive and exclusive bounds.
> - No partitioning scheme survives first contact with reality. So you will > need a facility for splitting and joining existing partitions. For > splitting partitions, it's sufficient to require that the new partition > share either a upper/lower bound (with the same inclusivity/exclusivity) of > an existing partition, thus uniquely identifying the partition to be split, > and require that the other bound be within the range of the partition to be > split. Similarly, it's fair to require that the partitions to be joined be > adjacent in range. In both cases, range operators make these tests simple. >
SPLIT/MERGE can be done in later patches/release, I think.
Later patches for sure. When a partition "fills up", it's a critical performance issue, so the fewer steps needed to amend it the better.
