Tonights Greenplum error was
ERROR: could not find segment file to use for inserting into relation table (64749). (appendonlywriter.c:569) SQL state: XX000
Which essentially means game over. Dump your table and recreate it, because you won’t be able to put any more data into it. Luckily you can still pull it out. This seems to only happen to append only compressed tables in both 3.x and 4.x. It’s supposed to be fixed in an upcoming patch release. It’s still enough to make George Bush sad.