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3e3f8f2020
The code recorded cache invalidation events by zeroing the "localreloid" field of affected cache entries. However, it's possible for an inval event to occur even while we have the entry open and locked. So an ill-timed inval could result in "cache lookup failed for relation 0" errors, if the worker's code tried to use the cleared field. We can fix that by creating a separate bool field to record whether the entry needs to be revalidated. (In the back branches, cram the bool into what had been padding space, to avoid an ABI break in the somewhat unlikely event that any extension is looking at this struct.) Also, rearrange the logic in logicalrep_rel_open so that it does the right thing in cases where table_open would fail. We should retry the lookup by name in that case, but we didn't. The real-world impact of this is probably small. In the first place, the error conditions are very low probability, and in the second place, the worker would just exit and get restarted. We only noticed because in a CLOBBER_CACHE_ALWAYS build, the failure can occur repeatedly, preventing the worker from making progress. Nonetheless, it's clearly a bug, and it impedes a useful type of testing; so back-patch to v10 where this code was introduced. Discussion: https://postgr.es/m/1032727.1600096803@sss.pgh.pa.us
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. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.