Re: DB Normalisation

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Michel
ConnectRate is dependant on there being a Call, except weekend calls of
Local & National description are free. Thus both Rate & ConnectRate are 0 in
these cases.

I reckoned that records from 9 down could be separated out ,but am uncertain
how to make the Join.
Using Accesses Table Analyser throws up a solution but it proves difficult
to follow.

Cheers

--
allkenny


"Michel Walsh" wrote:

Hard to say, but it seems that ConnectRate is dependant of Rate, so I would
make a table, Rates, with fields Rate and ConnectRate, while this table,
chargesRates, will only get the Rate (since it seems we can get the
ConnectRate knowing only the Rate: if rate = 0, connectRate = 0, else,
connectRate = 6)).

Otherwise, your table seems already normalized, even if you can normalize it
further, but that may be excessive: using a table Descriptions, one field,
Description, 5 records: Local, National, Mobile, 840, 870; same with
DayParts, one field, dayPart, two records: Day, Evening; same with
Weekparts, one field, weekpart, two records: Weekday, Weekend. Normalization
is not a religion, neither an absolute science which stands all by itself:
it depends on the use you will make of your database. As example, if you
plan to have many 'situations' where the 'Description' will be implied,
then, the table Descriptions is probably required and normalization about it
is far from being excessive anymore, and probably become mandatory. On the
other hand, if 'Description' is not used anywhere else in your application,
then using a table Descriptions to store all its possible appearance in this
table is excessive, for the problem as it stands, today, even if it may be
nice in the future, if other requirements come to life. Fortunately, with
Access, it is easy to make such changes.


Vanderghast, Access MVP


"allkenny" <allkenny@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:AD3C5DD8-6C7A-4C50-B312-3B96C30195A8@xxxxxxxxxxxxxxxx

-- Being new to DB design can anyone suggest how to de-compose the
following
table?
tblChargeRates
CRID Descpt Daypart Weekpart Rate ConnectRate
1 Local Day Weekday 4 6
2 Local Evening Weekday 1.5 6
3 Local Day Weekend 0 0
4 Local Evening Weekend 0 0
5 National Day Weekday 4 6
6 National Evening Weekday 1.5 6
7 National Day Weekend 0 0
8 National Evening Weekend 0 0
9 Mobile Day Weekday 12 6
10 Mobile Evening Weekday 7 6
11 Mobile Day Weekend 12 6
12 Mobile Evening Weekend 7 6
13 845 Day Weekday 4 6
14 845 Evening Weekday 2 6
15 845 Day Weekend 4 6
16 845 Evening Weekend 2 6
17 870 Day Weekday 8 6
18 870 Evening Weekday 4 6
19 870 Day Weekend 8 6
20 870 Evening Weekend 4 6


Allkenny

.