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Here you are: It´s from Oracle8 Server Concepts:
Internal Numeric Format
Oracle stores numeric data in variable-length format. Each value is stored
in scientific notation, with one byte used to store the exponent and up to
20 bytes to store the mantissa. (The resulting value is limited to 38 digits
of precision.) Oracle does not store leading and trailing zeros. For
example, the number 412 is stored in a format similar to 4.12 x 10^2, with
one byte used to store the exponent (2) and two bytes used to store the
three significant digits of the mantissa (4, 1, 2).
Taking this into account, the column data size for a particular numeric data value NUMBER (p), where p is the precision of a given value (scale has no effect), can be calculated using the following formula:
1 byte (exponent) + FLOOR(p/2)+1 bytes (mantissa) + 1 byte (only for a negative number where the number of significant digits is less than 38) _______________________
Zero and positive and negative infinity (only generated on import from Version 5 Oracle databases) are stored using unique representations: zero and negative infinity each require one byte; positive infinity requires two bytes.
Louis Frolio <frolio_at_videoshare.com> escribió en el mensaje de noticias
87ps2c$enr$1_at_bob.news.rcn.net...
> Greetings All, I was hoping that someone might be able to tell
> me how many bytes the datatype "number" uses. If it is dynamic
> what is the method of determinig how many bytes will be used?
>
>
> Thank You, Louis
> frolio_at_videoshare.com
>
>
Received on Mon Mar 20 2000 - 12:14:41 CST