Horton

Re: [HACKERS] [PATCH] Generic type subscripting

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
Cc: Dmitry Dolgov <9erthalion6@gmail.com>, Pavel Stehule <pavel.stehule@gmail.com>, Alexander Korotkov <aekorotkov@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>, David Steele <david@pgmasters.net>, Nikita Glukhov <n.gluhov@postgrespro.ru>, Alvaro Herrera <alvherre@2ndquadrant.com>, David Fetter <david@fetter.org>, Thomas Munro <thomas.munro@gmail.com>, Oleksandr Shulgin <oleksandr.shulgin@zalando.de>, Robert Haas <robertmhaas@gmail.com>, Michael Paquier <michael.paquier@gmail.com>, Oleg Bartunov <obartunov@gmail.com>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2020-12-07T22:25:41Z
Lists: pgsql-hackers 
Andres Freund <andres@anarazel.de> writes:
> On 2020-12-07 16:32:32 -0500, Tom Lane wrote:
>> What did you think of the idea of merging EEOP_SBSREF_OLD / ASSIGN / FETCH
>> into a single step type distinguished only by the callback function?

> I don't have a strong opinion on this. I guess find it a bit easier to
> understand the generated "program" if the opcodes are distinct (I've a
> pending patch printing the opcode sequence). Especially as the payload
> is just function pointers.
> So I think I'd just merge the *implementation* of the steps, but leave
> the different opcodes around?

Fair enough.  It wasn't entirely clear to me whether it'd be kosher to
write
		EEO_CASE(EEOP_SBSREF_OLD)
		EEO_CASE(EEOP_SBSREF_ASSIGN)
		EEO_CASE(EEOP_SBSREF_FETCH)
		{
			// do something
			EEO_NEXT();
		}

I can see that that should work for the two existing implementations
of EEO_CASE, but I wasn't sure if you wanted to wire in an assumption
that it'll always work.

			regards, tom lane

Commits

  1. Throw error when assigning jsonb scalar instead of a composite object

  2. Filling array gaps during jsonb subscripting

  3. Implementation of subscripting for jsonb

  4. Allow ALTER TYPE to update an existing type's typsubscript value.

  5. Allow subscripting of hstore values.

  6. Support subscripting of arbitrary types, not only arrays.

  7. jit: Reference function pointer types via llvmjit_types.c.

  8. Teach contain_leaked_vars that assignment SubscriptingRefs are leaky.

  9. jit: Correct parameter type for generated expression evaluation functions.

  10. Renaming for new subscripting mechanism

  11. Fix assertion failure for SSL connections.

  12. Teach eval_const_expressions() to handle some more cases.