Re: DATA SAMPLED ON TIME

In my opinion, the key decision on whether you should use vararray is how you plan to retrieve the data. A good idea would be to find out what queries will be used, create some test data and see how it will work out. For example, you may have some frequent queries for which you need to create an index, maybe you need some daily reports, for example. If you must do a full table scan for each result, performance might be unacceptable. You may find that you need to create some summary tables, etc. I would consider partitioned tables to give you more flexibility. A single 280-gig. table would be difficult to manage. If you had 1-month partitions, for example, that is a mere 24-gig each. Then once you have completed a year, you should be able to remove the oldest month to make room for the next month. In article <8ircne$kjh$1_at_nslave2.tin.it>,   "maurizio" <mrzgnv_at_tin.it> wrote:
> Hello,
> my name is Maurizio and i have a problem.
>
> I must to store in Oracle 8i DB on WNT a lot of data acquired by a
 Data
> Acquisition System (DAS) for a coil galvanization line plant.
>
> I must to store all data acquired for one year.
>
> The plant process 24 h/day about 4 coils per heure with maximum
 length of
> 8000 meters.
>
> After the coil is processed the DAS send to me the data acquired (250
> measured for each meter of coil coming form 250 different sensors).
>
> In order to save that information into DB i created a table and i
 used a
> VARRAY dimensioned to 8000 elements:
>
> create type SAMPLE DATA as varray(8000) of number(5)
>
> create table COIL_OUT_DATA (
> COIL_ID number(4) not null [ 1 year of
> coils]
> MEASURE_ID number(4) not null [1..250]
> DATA SAMPLE_DATA [8000 elements]
> primary key (COILD_ID, MEASURE_ID)
> );
>
> In this way for each coil i have 250 very big records (for each coil
 about
> 250*(8002)*4 Byte = 8MB)
>
> In one year i will have 365day*24heures*4coilperheure*8 MB = 280 GB
 of
> data.
>
> My questions are:
> 1) Is the VARRAY a good solution for my application?
> 2) After one year DB will be too big?
>
> Someone has other solution?
>
>

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Before you buy. Received on Fri Jun 23 2000 - 00:00:00 CDT