fd5a1a0c3e
This enhancement builds upon the infrastructure introduced in commit 228c370868, which enables the preservation of deleted tuples and their origin information on the subscriber. This capability is crucial for handling concurrent transactions replicated from remote nodes. The update introduces support for detecting update_deleted conflicts during the application of update operations on the subscriber. When an update operation fails to locate the target row-typically because it has been concurrently deleted-we perform an additional table scan. This scan uses the SnapshotAny mechanism and we do this additional scan only when the retain_dead_tuples option is enabled for the relevant subscription. The goal of this scan is to locate the most recently deleted tuple-matching the old column values from the remote update-that has not yet been removed by VACUUM and is still visible according to our slot (i.e., its deletion is not older than conflict-detection-slot's xmin). If such a tuple is found, the system reports an update_deleted conflict, including the origin and transaction details responsible for the deletion. This provides a groundwork for more robust and accurate conflict resolution process, preventing unexpected behavior by correctly identifying cases where a remote update clashes with a deletion from another origin. Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: shveta malik <shveta.malik@gmail.com> Reviewed-by: Nisha Moond <nisha.moond412@gmail.com> Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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