When constructing the segment_info view, we can no longer do a natural join
on the block_index and segments tables, since the segments table recently
acquired a checksum column. Now explicitly join on the segmentid column
only, which is the desired behavior (and what a natural join used to do).
create view segment_info as select * from
(select segmentid, max(timestamp) as mtime,
sum(size) as size, count(*) as objects
- from block_index natural join segments group by segmentid)
+ from block_index join segments using (segmentid) group by segmentid)
natural join
(select segmentid, sum(size) as used, count(*) as objects_used
from block_index where blockid in