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NULL/Varchar and extra bits

How may extra bits does a NULL column contain.
And how many extra bits does a varchar column contain.

(I 've worked with Ingres and in that environment it both needed 2 extra
bits)

Bye,

Arno de Jong, The Netherlands
Jul 20 '05 #1
2 2475
See inline

"A.M. de Jong" wrote:

How may extra bits does a NULL column contain.
None. There will always be one bit for each column in the NULL-bitmap,
regardless of whether the column contains or allows NULLs.
And how many extra bits does a varchar column contain.
Each varchar column uses a 2 byte size indicator. A char column does not
have this overhead because of its fixed size.

Gert-Jan
(I 've worked with Ingres and in that environment it both needed 2 extra
bits)

Bye,

Arno de Jong, The Netherlands

Jul 20 '05 #2
Hi Gert-Jan,

Can we continue in dutch; privately ??

Arno de Jong

"Gert-Jan Strik" <so***@toomuchspamalready.nl> wrote in message
news:3F***************@toomuchspamalready.nl...
See inline

"A.M. de Jong" wrote:

How may extra bits does a NULL column contain.


None. There will always be one bit for each column in the NULL-bitmap,
regardless of whether the column contains or allows NULLs.
And how many extra bits does a varchar column contain.


Each varchar column uses a 2 byte size indicator. A char column does not
have this overhead because of its fixed size.

Gert-Jan
(I 've worked with Ingres and in that environment it both needed 2 extra
bits)

Bye,

Arno de Jong, The Netherlands

Jul 20 '05 #3

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