2b75c38b70
This polymorphic function produces an error if the input value is detected as being the null value; otherwise it returns the input value unchanged. This function can for example become handy in SQL function bodies, to enforce that exactly one row was returned. Author: Joel Jacobson <joel@compiler.org> Reviewed-by: Vik Fearing <vik@postgresfriends.org> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/ece8c6d1-2ab1-45d5-ba12-8dec96fc8886@app.fastmail.com Discussion: https://postgr.es/m/de94808d-ed58-4536-9e28-e79b09a534c7@app.fastmail.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/.