pg_lo_read() reads at most len (defaults to 8192) bytes from a large object and returns it as a string. large_object specifies a valid large object resource andlen specifies the maximum allowable size of the large object segment. It returns FALSE if there is an error.
To use the large object (lo) interface, it is necessary to enclose it within a transaction block.
Note: This function used to be called pg_loread().