This command loads a shared library file into the PostgreSQL server's address space. If the file has been loaded already, the command does nothing. Shared library files that contain C functions are automatically loaded whenever one of their functions is called. Therefore, an explicit LOAD is usually only needed to load a library that modifies the server's behavior through "hooks" rather than providing a set of functions.
The file name is specified in the same way as for shared library names in CREATE FUNCTION; in particular, one can rely on a search path and automatic addition of the system's standard shared library file name extension. See Section 34.9 for more information on this topic.
Non-superusers can only apply LOAD to library files located in $libdir/plugins/ — the specified filename must begin with exactly that string. (It is the database administrator's responsibility to ensure that only "safe" libraries are installed there.)