Re: Informix vs. Sybase vs. Oracle vs. (gasp) MS SQL Server

Anthony Mandic wrote: > > David Williams wrote: > > > Imagine 1 page with 2 rows one it. > > > > 1. Page level locking > > > > User A updates row 1 > > At the same time user B updates row 2. User B has to wait for > > User B to commit. > > You're forgetting latency. There's no way that you'd ever > get immediate concurrency as in your second scenario below. How about a multi-processor system with a multi-threaded db server? > > Lock granularity is still a problem. Why do UNIX kernels lock > > individual files and data structures rather than having one large > > kernel lock? Try reading > > Hey but they don't lock rows of text in a file do they? There is no such thing as a row of text in a UNIX file. They are nothing by streams of bytes.