ChristopherSchultz commented on PR #596: URL: https://github.com/apache/tomcat/pull/596#issuecomment-1462052065
> @ChristopherSchultz Is there a list of supported database systems with which the DataSourceStore is compatible? Are you sure that they all support "SELECT FOR UPDATE"? I tried to look that up and the "best" thing I found was https://www.sql-workbench.eu/dbms_comparison.html Good question. I was originally going to use `MERGE` but the database I have at-hand (MariaDB) doesn't support it, so I went with `SELECT...FOR UPDATE`. It's not clear to me if the `SELECT...FOR UPDATE NOWAIT` listed in that table is specifically talking about the `NOWAIT` part of the query. For example, I know that both MariaDB and MySQL have supported `SELECT...FOR UPDATE` for a long time, but the entry for MySQL states "_Since 8.0_" and MariaDB says "_No_". A quick check of the [HSQLDB Documentation](http://hsqldb.org/doc/2.0/guide/dataaccess-chapt.html#dac_jdbc_cursor_updatability) shows that `SELECT...FOR UPDATE` is available while that list claims it is not supported. Same thing with [IBM DB2](https://www.ibm.com/docs/en/informix-servers/12.10?topic=statement-update-clause) and [SQL Server](https://learn.microsoft.com/en-us/sql/odbc/reference/appendixes/processing-select-for-update-statements?view=sql-server-ver16). But it's clear that not all RDMBSs support that syntax. Maybe it's not possible to write a single code-path to satisfy all major RDBMS systems. I'd be happy to change the PR to offer a selection between the two via configuration. -- 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. To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
