Data modelling discussion (LONG)
Date: 27 Jul 94 19:28:25 -0500
Message-ID: <1994Jul27.192825.1_at_ashley.cofc.edu>
Basic database design question, one which (currently, to my knowledge) has two camps:
Gas Chromatography: for each run
for each analyte, i.e. Benzene
attribute 1: concentration
attribute 2: retention time
attribute 3: area count
attribute N: etc
Inductively Coupled Plasma: for each run
for each analyte, i.e. Silver
attribute 1: concentration
attribute 2: emission counts
attribute 3: number of replicates
attribute 4: spectral line used
attribute N: etc
Gamma Spectroscopy: for each run
for each isotope: i.e. Uranium-235
attribute 1: concentration
attribute 2: Minimim Detectable activity
attribute 3: counts
attribute 4: detector efficiency
- Create a 2 table structure, with a run and results format. The run table is the master table, with a many to one relationship with the results table. The results table is designed with lots of generic numeric fields. (i.e. it looks like the following: table results ( runid number references run.runid, field1 number, field2 number, field3 number, ... fieldN number) where the number of fields is the largest number of field required for the most data intensive instrument. Many views are created to support this structure, which each directed to the fields applicable to that particular type of instrument, with field aliases appropriate to the type of data in that field.
- Create a 3 table structure, with a run,parameter,and attributes
format. The run is the master to the parameter, and the parameter
is the master to the attributes. The relationship is as follows:
run.runid = parameter.runid, a one to many
attributes.runid = parameter.runid and attributes.parmname
- parameter.parmname a many to one relationship. Each parameter constitutes a row in this table.
So which is better? Are there any other options I may be missing. It seems
that this problem BEGS for a object oriented RDBMS. Each row could be a
different object, each of which unique attributes specific to the type
of data it contained. How best can this be "simulate" using current
technology.
Please comment as to any other ideas you may have re this issue. If
I am too vague to promote discussion, please say so.
TIA
alan johnson
General Engineering Labs
Charleston, S.C.
alan.johnson_at_gel.com
johnsona_at_ashley.cofc.edu
Received on Thu Jul 28 1994 - 02:28:25 CEST