Mariel Cherkassky wrote: > thank you for the explanation but I still got a few questions about this subject : > 1.By physical location of the data do you mean the location on disk of the objects? > I mean i thought that the wal files containing the logical changes , for example > If I run an update then the wal file will contain the update in some format. > Can you explain then what exactly it contains and what you meant by physical ? It does *not* contain the SQL executed - how'd that work with functions like "random"? Rather, the information is like "replace the 42 bytes from offset 99 of block 12 in file xy with these bytes: ...". > 2.So If the vacuum full stopped in some brutal way (kill -9 or the disk run of space) > does all the new data files that are created deleted or left on the storage as orphan files ? In an out of space scenario, the files would get removed. If you kill -9 the backend they will be left behind. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
