Jeff Davis <pgsql@xxxxxxxxxxx> writes: > On Tue, 2006-10-03 at 00:42 +0200, Alexander Staubo wrote: >> Why does pg_dump serialize data less efficiently than PostgreSQL when >> using the "custom" format? > What you're saying is more theoretical. If pg_dump used specialized > compression based on the data type of the columns, and everything was > optimal, you're correct. There's no situation in which the dump *must* > be bigger. However, since there is no practical demand for such > compression, and it would be a lot of work ... There are several reasons for not being overly tense about the pg_dump format: * We don't have infinite manpower * Cross-version and cross-platform portability of the dump files is critical * The more complicated it is, the more chance for bugs, which you'd possibly not notice until you *really needed* that dump. In practice, pushing the data through gzip gets most of the potential win, for a very small fraction of the effort it would take to have a smart custom compression mechanism. regards, tom lane
