mt1p@VOLGA.EDRC.CMU.EDU (Michael Terk) (06/01/88)
I am very new to using Informix. Actually all that I have done is to create
a database and some tables and now I want to perform some queries. The
problem I came up against, is that the reference guide to RSQL or ESQL does
not say that I can use C functions such as sqrt,sin,cos in the WHERE clause
of the SELECT statement. The application I am working on requires that I
find an entry in a table that satisfies something like
(bf * (sqrt (tf / d)) >= 1200 and
(d ** tw) / 12000 >= 200
with the objective function of MIN(d). I need to find out how easialy are
these things done in Informix, so I can either continue working with it, or
switch to another DBMS. Any help will be greatly appreciated.
Thanks,
Mike Terkbobd@bloom.UUCP (Bob Donaldson) (06/02/88)
In article <1811@pt.cs.cmu.edu>, mt1p@VOLGA.EDRC.CMU.EDU (Michael Terk) writes: > of the SELECT statement. The application I am working on requires that I > find an entry in a table that satisfies something like > (bf * (sqrt (tf / d)) >= 1200 and > (d ** tw) / 12000 >= 200 > with the objective function of MIN(d). I need to find out how easialy are > these things done in Informix, so I can either continue working with it, or > switch to another DBMS. Any help will be greatly appreciated. I don't know about Informix, but we have done similar things with Empress/32 (runs under Unix on most anything, under VMS on VAX, under DOS on PC/AT). It requires a little customization, but that is a strength of Empress: it lets you bind in your own C functions and define them to SQL so they can be used in either the select clause or the where clause. VERY helpful for scientific applications!! ---------------------------------------------------------------- Bob Donaldson ...!ut-emx!juniper!radian!bobd Radian Corporation PO Box 201088 (512) 454-4797 Austin, TX 78703 Views expressed are my own, not necessarily those of my employer.
bobb@netcom.UUCP (Bob Beaulieu) (03/03/90)
I am currently using Informix 3.3 on a Plexus P/60 and having trouble with float field and roundings. Ex. If I imput the data as 2.3, it ends up with a value of 2.98799963...? Why can't it just be 2.3? This is difficult when acegos are looking for a value of 2.3 and doesn't see it. Has anyone experienced this problem and any solutions available? Thanks for your help. Bob B. -- o\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\o o Bob Beaulieu 277-b Tyrella Avenue o o Mountain View, CA 94043 o o (415) 967-4678 o o uunet!apple!netcom!beau o o\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\/\\o