On 2018-Dec-20, Robert Haas wrote: > On Thu, Dec 20, 2018 at 3:58 PM Alvaro Herrera <alvhe...@2ndquadrant.com> > wrote: > > I think what prompted the lock to be AccessShareLock for the child rel > > in the first place is the fact that ATExecDropInherit() (ALTER TABLE NO > > INHERIT) uses AccessShare for the *parent* relation. > > Seems like apples and oranges,
Yes, but I can understand someone looking at ATExecDropInherit while writing ATExecDetachRelation and thinking "ah, I have to grab AccessShareLock on the other relation" without stopping to think in what direction the parenthood between the rels goes. > and also maybe not that safe. I think it's strange, but I'm not interested in analyzing that at this time. Its comment do say that DROP TABLE (of the child, I surmise) does not acquire *any* lock on the parent, which is also strange. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
