Re: How many bytes does the datatype NUMBER use?

Hello, spencer

spencer wrote:
>

... [skipped]

> When I created an INDEX on test_col, the index used
> significantly more
> space than the original table. Also, the total amount of space
> allocated
> to the index did not seem to vary with the values loaded into
> the table,
> like the average row length of the table did.
>
> This leads me to believe that the representation of a NUMBER in
> an index
> datablock may not be identical to representation in the table
> datablock.
> Possibly, in an INDEX, a NUMBER may be represented as a constant
> 22 bytes. If so, this probably is a performance issue...
>

Representation of NUMBER in an index datablock IS identical to one in a table datablock. You should take into account that index entry has such structure: [KEY VALUE, ROWID] Overhead of ROWID is the reason of difference between table and index size.

Hope this info can be useful for you.

   Regards,

   Igor

--
Ranum's Law: "You can't solve social problems with software". Received on Wed Feb 09 2000 - 13:04:26 CST