Re: jsonb_delete with arrays

> On 15 November 2016 at 22:53, Magnus Hagander <magnus(at)hagander(dot)net> wrote:
> Attached is an implantation of jsonb_delete that instead of taking a
single key to remove accepts an array of keys (it still does just keys, so
it's using the - operator, it's not like the path delete function that also
takes an array, but uses a different operator).
>
> In some simple testing of working through a real world usecases where we
needed to delete 7 keys from jsonb data, it shows approximately a 9x
speedup over calling the - operator multiple times. I'm guessing since we
copy a lot less and don't have to re-traverse the structure.

I wonder, is it worth it to create some sort of helper function to handle
both
deleting one key and deleting an array of keys (like `setPath` for
`jsonb_set`,
`jsonb_insert` and `jsonb_delete_path`)? At first glance it looks like
`jsonb_delete` and `jsonb_delete_array` can reuse some code.

Speaking about the performance I believe it's the same problem as here [1],
since for each key the full jsonb will be decompressed. Looks like we need a
new set of functions to read/update/delete an array of elements at once.

[1]:
https://www.postgresql.org/message-id/flat/1566eab8731.10193ac585742.5467876610052746443%40zohocorp.com