28.4. Server-Side Functions

There are two built-in server-side functions, lo_import and lo_export, for large object access, which are available for use in SQL commands. Here is an example of their use:

CREATE TABLE image (     name            text,     raster          oid );  INSERT INTO image (name, raster)     VALUES ('beautiful image', lo_import('/etc/motd'));  SELECT lo_export(image.raster, '/tmp/motd') FROM image     WHERE name = 'beautiful image';

These functions read and write files in the server's file system, using the permissions of the database's owning user. Therefore, their use is restricted to superusers. (In contrast, the client-side import and export functions read and write files in the client's file system, using the permissions of the client program. Their use is not restricted.)