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Date: Thu, 30 Nov 2023 08:10:14 +0900
Message-ID: <6A2118D9-6DD0-4273-A2C0-A1088C05314D@sakiot.com>
To: PHP internals <internals@lists.php.net>
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Subject: [PDO] 2 phase commit
From: saki@sakiot.com (Saki Takamachi)

Hi internals,

For the past few days I've been thinking about whether to make a suggestion t=
o add two-phase commit functionality to pdo.

I would like to hear everyone's opinions.


About two-phase commit
Regular transactions do not guarantee consistency across multiple DBs. For e=
xample, if you update DB1 and DB2 at the same time, only DB1 may be updated a=
nd the DB2 update may fail.

When using two-phase commit, it is as if a common transaction has been start=
ed for multiple DBs, and their consistency can be guaranteed.

Currently, pdo does not have such a feature as a method, but it is possible t=
o use two-phase commit by executing a query. Think of it as adding such func=
tionality as a method.

Although I have only written about the advantages, two-phase commit also has=
 disadvantages, such as the possibility that locks may not be released forev=
er under certain conditions.

Regards.

Saki=