Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!apple!voder!blia!miket From: miket@blia.BLI.COM (Mike Tossy) Newsgroups: comp.databases Subject: Re: Parsing Query Languages in the Client or Server Message-ID: <9463@blia.BLI.COM> Date: 25 Sep 89 22:49:20 GMT References: <6155@sybase.sybase.com> <6167@sybase.sybase.com> <1989Sep24.215650.15732@odi.com> Organization: Britton Lee, Los Gatos, CA Lines: 56 > > > At Britton Lee (ShareBase) > > query languages were parsed in the clients and parse trees were sent > > to the server. Here at Sybase we send the query language to the > > server to be parsed. > (Note the use of past tense. This is changing for exactly the reasons outlined below.) > > ... The world is moving toward > open, standardized interfaces. There is already an ANSI SQL standard, > and a subcommittee of ANSI X3H2 is working on remote database access > protocols. Eventually, a client will be able to run queries on anyone's > server without having to know much about the server. > > (For completeness let me offer these comments): One argument in favor of parsing (or at least scanning) on the client: Imagine a network with hundreds of clients talking to a few servers. The clients represent a very valuable source of MIPS - MIPS which are fairly difficult to apply to the core of the RDBMS problem, but which are easy to apply to the scanning/parsing problem. In this scenerio a server which used server based scanning/parsing would need to be bigger than a server that used client based scanning/parsing. Another argument in favor of client based scanning/parsing: Precompiler code probably needs to be scanned on the client anyway; so using a server based scanning/parsing system results in double scanning. Personnally I think a good case can be made for either side; but the new standards are going toward scanning/parsing on the server and therefore it is the existance of a standard, not the merits of the technical argument that will decide where to do the parsing. (I am reminded of the time C.J. Date was a guest at our user's group and one customer asked if SQL or QUEL was the better langauge (we offer both). Date responded "QUEL, but it doesn't matter; SQL is the standard"). Final note: parsing on the client does NOT mean you can use a dumb terminal connected directly to a server. You still need "smarts" on the client end. Mike Tossy ShareBase Coropration miket@blia.bli.com 14600 Wichester Blvd (408) 378-7575 ext2200 Los Gatos, CA 95030 (Formerly: Britton Lee, Inc.) The preceeding might or might not be close to the opinion of ShareBase Corp; if you think I bothered to clear it with anybody other than myself you're crazy.