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MemoryContextContains is no longer reliable in the wake of c6e0fe1f2, so we need to get rid of these uses. It appears that there's no really good reason to force the result of an aggregate's finalfn or serialfn to be allocated in the per-tuple context. The only other plausible case is that the result points to or into the aggregate's transition value, and that's fine because it will last as long as we need it to. (This conclusion depends on the assumption that finalfns are not allowed to scribble on the transition value, but we've long required that.) So we can just drop the MemoryContextContains plus datumCopy business, although we do need to take care to not return a read-write pointer when the transition value is an expanded datum. Likewise, we don't really need to force the result of a window function to be in the output context. In this case, the plausible alternative is that it's pointing into the temporary tuple slot used by WinGetFuncArgInPartition or WinGetFuncArgInFrame (since those functions could return such a pointer, which might become the window function's result). That will hold still for long enough, unless there is another window function using the same WindowObject. I'm content to always perform a datumCopy when there's more than one such function. On net, these changes should provide small speed improvements as well as removing problematic code. Tom Lane and David Rowley Discussion: https://postgr.es/m/1913788.1664898906@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/.