Comments on SDD-1 concurrency control mechanisms
Gordon McLean · ACM Transactions on Database Systems · 1981
In [2] and [3], Bernstein et al. discuss concurrency control mechanisms in the distributed database management system SDD-1.The concurrency monitor sketched in [3] is subject to distributed deadlock, as the following example demonstrates.References [2] and [33 contain several other less significant errors, which are also noted herein.DEADLOCK EXAMPLE Consider the following SDD-1 database design.(The notation used here is that * Gordon McLean (5) In [2, p. 66, first paragraph of proof of Lemma PATH], "If classof(i[O]) is not a P2-class, . .." should read "If classof(i[O]) does not run P4, . .."ACKNOWLEDGMENT The author thanks Phil Bernstein for his persistent encouragement and thoughtful comments.