Message-ID: <b5eacfb7-ea65-64c2-1a5a-459341ee16b7@iki.fi>
Date: Fri, 30 Jun 2023 17:26:57 +0300
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Subject: Re: SPI isolation changes
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To: Seino Yuki <seinoyu@oss.nttdata.com>, pgsql-hackers@lists.postgresql.org
References: <295eeac9054979182770bdf9d72d28d3@oss.nttdata.com>
From: Heikki Linnakangas <hlinnaka@iki.fi>
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On 30/06/2023 17:15, Seino Yuki wrote:
> Hi,
> 
> When I read the documents and coding of SPI, [1]
> I found that the following the SPI_start_transaction does not support
> transaciton_mode(ISOLATION LEVEL, READ WRITE/READ ONLY) like BEGIN
> command. [2]
> Is there a reason for this?

Per the documentation for SPI_start_transaction that you linked to:

"SPI_start_transaction does nothing, and exists only for code 
compatibility with earlier PostgreSQL releases."

I haven't tested it, but perhaps you can do "SET TRANSACTION ISOLATION 
LEVEL" in the new transaction after calling SPI_commit() though. Or "SET 
DEFAULT TRANSACTION ISOLATION LEVEL" before committing.

-- 
Heikki Linnakangas
Neon (https://neon.tech)