Paolo wrote: > Hi, > I've read 2.4.2 docs and past messages, but found not a real answer.
> Is there a performance reason, future (un)support, cleaniness, ... to > switch from > "time_iso char(16) NOT NULL," > to > "time_iso TIMESTAMP NOT NULL DEFAULT 0," > ?? > I can't see a good reason, except for a more understandable DB > maintenance query. Since we're going to recreate the MySQL DB, I'd like > to pick the layout that is going to last longer... > Hints? > Paolo My impression is (and I could be wrong) that msgs.time_iso was originally created with the assumption that a field like that may be used at some time in the future and it would be better to have it and not need it than to need it and not have it. It looks like PostgreSQL later took advantage of its existence. It got left there as char(16) simply for consistency (and possibly because you must set it up differently for PostgreSQL and MySQL). It appears the MySQL queries most often use msgs.time_num - but can use msgs.time_iso (TIMESTAMP) as an alternative if the scripts are modified to use it. I think time_iso char(16) is not really of much use and ends up being a a kind of placeholder. If time_iso is created as TIMESTAMP NOT NULL DEFAULT 0 (and indexed) then it can be used as a basis for comparison, but I don't know that there is any advantage over msgs.time_num. I would guess that indexing on both would not be a benefit so I'm guessing you would index on one or the other, and set up your scripts to use the one you choose to index. Like I said, I could be wrong. Gary V Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ AMaViS-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/amavis-user AMaViS-FAQ:http://www.amavis.org/amavis-faq.php3 AMaViS-HowTos:http://www.amavis.org/howto/
