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ASF GitHub Bot logged work on BEAM-12044: ----------------------------------------- Author: ASF GitHub Bot Created on: 25/Mar/21 18:58 Start Date: 25/Mar/21 18:58 Worklog Time Spent: 10m Work Description: aromanenko-dev commented on a change in pull request #14338: URL: https://github.com/apache/beam/pull/14338#discussion_r601762732 ########## File path: sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java ########## @@ -903,6 +903,8 @@ public void processElement(ProcessContext context) throws Exception { if (connection == null) { connection = dataSource.getConnection(); } + // PostgreSQL requires autocommit to be disabled to enable cursor streaming Review comment: I'd suggest to set it to `false` only if it was not explicitly set to `true` by connection properties configuration. Otherwise, it won't be possible to override and it can be confusing for users (since we already provide a way to do that with `DataSourceConfiguration`). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org Issue Time Tracking ------------------- Worklog Id: (was: 572211) Time Spent: 1h 20m (was: 1h 10m) > JdbcIO should explicitly setAutoCommit to false > ----------------------------------------------- > > Key: BEAM-12044 > URL: https://issues.apache.org/jira/browse/BEAM-12044 > Project: Beam > Issue Type: Bug > Components: sdk-java-core > Affects Versions: 2.28.0 > Reporter: Sylvain Veyrié > Priority: P2 > Time Spent: 1h 20m > Remaining Estimate: 0h > > Hello, > Per [PostgreSQL JDBC > documentation|https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor], > autocommit must be explicitly disabled on the connection to allow cursor > streaming. > [~jkff] mentionned it [on the mailing > list|https://www.mail-archive.com/dev@beam.apache.org/msg16808.html], however > even if there is: > {code:java} > poolableConnectionFactory.setDefaultAutoCommit(false); > {code} > in JdbcIO:1555, currently, at least with JDBC driver 42.2.16, any read with > JdbcIO will memoize the whole dataset (which leads to OOM), since > {code:java} > connection.getAutoCommit() > {code} > returns true in JdbcIO#ReadFn#processElement. > I can provide a PR — the patch is pretty simple (and solves the problem for > us in 2.28.0): > {code:java} > if (connection == null) { > connection = dataSource.getConnection(); > } > connection.setAutoCommit(false); // line added > {code} > Thanks! -- This message was sent by Atlassian Jira (v8.3.4#803005)