Re: partition tree inspection functions

On 6/28/18 10:59, Amit Langote wrote:
> On 2018/06/28 17:40, Peter Eisentraut wrote:
>> On 6/26/18 07:08, Amit Langote wrote:
>>> As discussed a little while back [1] and also recently mentioned [2], here
>>> is a patch that adds a set of functions to inspect the details of a
>>> partition tree. There are three functions:
>>>
>>> pg_partition_parent(regclass) returns regclass
>>> pg_partition_root_parent(regclass) returns regclass
>>> pg_partition_tree_tables(regclass) returns setof regclass
>>
>> Does this add anything over writing a recursive query on pg_inherits?
>
> As far as the information output is concerned, it doesn't.

I'm thinking, an SQL query might be more efficient if you want to
qualify the query further. For example, give me all tables in this tree
that match '2018'. If you wrote your functions as SQL-language
functions, the optimizer could perhaps inline them and optimize them
further.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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