Specifically, add a per-node hook that is called after the per-node information has been displayed but before we display children, and a per-query hook that is called after existing query-level information is printed. This assumes that extension-added information should always go at the end rather than the beginning or the middle, but that seems like an acceptable limitation for simplicity. It also assumes that extensions will only want to add information, not remove or reformat existing details; those also seem like acceptable restrictions, at least for now. If multiple EXPLAIN extensions are used, the order in which any additional details are printed is likely to depend on the order in which the modules are loaded. That seems OK, since the user may have opinions about the order in which output should appear, and the extension author can't really know whether their stuff is more or less important to a particular user than some other extension. Discussion: http://postgr.es/m/CA+TgmoYSzg58hPuBmei46o8D3SKX+SZoO4K_aGQGwiRzvRApLg@mail.gmail.com Reviewed-by: Srinath Reddy <srinath2133@gmail.com> Reviewed-by: Andrei Lepikhov <lepihov@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Sami Imseih <samimseih@gmail.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.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.