Indexing of binary and varbinary

Hi

I’m writing an Alarms and Events database. Our A&E is identified by a byte
array in the A&E object.  This byte array I will store in a column of a tabl
e
in addition to other columns with other relevant data.

I’m thinking of using the binary or varbinary type for the purpose of
storing the byte array.

I also need to have an index on the varbinary field, -is that possible?

This field will identify an instance of a specific alarm and will be used to
calculate statistics regarding how often the alarm occurs etc.

Is possible to do SELECT on a varbinary, and if so is it more resource
demanding compared to do this with a string on the same size? (Another
possibility is to convert the byte array to a hex string).

SELECT BinId FROM Events WHERE BinId like @IdFromEvent
ORDER BY BinId

Regards
Kjell Arne

Hi

You can index varbinary columns,  but if you are going to always divide this
into individual bytes and want to mainly access these separately then you
would probably be better off holding them separately, expecially if you want
to index them separately. If the bytes represent characters then you should
hold them in char columns if they are numeric or binary they should be
numeric or binary.

HTH

John


"Kjell Arne Johansen" wrote:

> Hi
>
> I’m writing an Alarms and Events database. Our A&E is identified by a by
te
> array in the A&E object.  This byte array I will store in a column of a ta
ble
> in addition to other columns with other relevant data.
>
> I’m thinking of using the binary or varbinary type for the purpose of
> storing the byte array.
>
> I also need to have an index on the varbinary field, -is that possible?
>
> This field will identify an instance of a specific alarm and will be used 
to
> calculate statistics regarding how often the alarm occurs etc.
>
> Is possible to do SELECT on a varbinary, and if so is it more resource
> demanding compared to do this with a string on the same size? (Another
> possibility is to convert the byte array to a hex string).
>
> SELECT BinId FROM Events WHERE BinId like @IdFromEvent
> ORDER BY BinId
>
> Regards
> Kjell Arne