Message-ID: <gh-pgjdbc-pgjdbc-3678@github.com>
From: "vlsi (@vlsi)" <noreply+vlsi@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Mon, 16 Jun 2025 07:29:25 +0000
Subject: [pgjdbc/pgjdbc] PR #3678: fix: unable to open replication connection to servers < 12
List-Id: <gh-pgjdbc-pgjdbc.github.com>
X-GitHub-Author-Id: 213894
X-GitHub-Author-Login: vlsi
X-GitHub-Issue: 3678
X-GitHub-Labels: bug
X-GitHub-Repo: pgjdbc/pgjdbc
X-GitHub-State: merged
X-GitHub-Type: pull_request
X-GitHub-Url: https://github.com/pgjdbc/pgjdbc/pull/3678
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pgjdbc attempted issuing SET extra_float_digits for servers of versions less than 12, while the replication protocol does not allow set ... commands.

It resulted in the following [connection failure](https://github.com/pgjdbc/pgjdbc/actions/runs/15672177908/job/44145122287?pr=3668#step:8:991):

    org.postgresql.util.PSQLException: ERROR: syntax error
        at app//org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2736)
        at app//org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2421)
        at app//org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:372)
        at app//org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:330)
        at app//org.postgresql.core.SetupQueryRunner.run(SetupQueryRunner.java:57)
        at app//org.postgresql.core.v3.ConnectionFactoryImpl.runInitialQueries(ConnectionFactoryImpl.java:1031)
        at app//org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:358)
        at app//org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:57)
        at app//org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:277)
        at app//org.postgresql.Driver.makeConnection(Driver.java:448)
        at app//org.postgresql.Driver.connect(Driver.java:298)
        at platform/java.sql@21.0.7/java.sql.DriverManager.getConnection(DriverManager.java:683)
        at platform/java.sql@21.0.7/java.sql.DriverManager.getConnection(DriverManager.java:191)
        at app//org.postgresql.test.TestUtil.openDB(TestUtil.java:356)
        at app//org.postgresql.test.TestUtil.openReplicationConnection(TestUtil.java:338)
        at app//org.postgresql.replication.CopyBothResponseTest.setUp(CopyBothResponseTest.java:60)