Re: post-freeze damage control - Mailing list pgsql-hackers

From Alena Rybakina
Subject Re: post-freeze damage control
Date
Msg-id 98403b80-11c2-4f90-a332-e2a01b709a1a@yandex.ru
Whole thread Raw
In response to Re: post-freeze damage control  (Alena Rybakina <lena.ribackina@yandex.ru>)
List pgsql-hackers

Sorry, I've just noticed that the letter is shown incorrectly. I rewrote it below.

As I understand it, you talked about speeding up SeqScan by faster re-searching through the use of a hash table. At the same time, we have to build it before that, when there was the initial lookup tuples, right?

I found this information in the ExecEvalHashedScalarArrayOp function, and I assume you meant this function in your message, right?

But I couldn't find information, when you told about cycling a long-expression on each incoming tuple. Could you ask me what function you were talking about or maybe functionality? I saw ExecSeqScan function, but I didn't see it.

On 18.06.2024 13:05, Alena Rybakina wrote:

Hi! Unfortunately, I was not able to fully understand your message. Could you explain it to me please?

On 09.04.2024 16:20, Andrei Lepikhov wrote:
 
Moreover, it helps even SeqScan: attempting to find a value in the hashed array is much faster than cycling a long-expression on each incoming tuple.

As I understand it, you talked about speeding up SeqScan by faster re-searching through the use of a hash table. At the same time, we have to build it before that, when there was the initial lookup tuples, right?

I found this information in the ExecEvalHashedScalarArrayOp function, and I assume you meant this function in your message.

But I couldn't find information, when you told about cycling a long-expression on each incoming tuple. Could you ask me what function you were talking about or maybe functionality? I saw ExecSeqScan function, but I didn't see it.

-- 
Regards,
Alena Rybakina
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company
-- 
Regards,
Alena Rybakina
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company

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