Thread

Re: [HACKERS] Savepoints... (row overhead)

Zeugswetter Andreas <andreas.zeugswetter@telecom.at> — 1999-06-17T16:16:26Z

> > If now we'll add 6 bytes to header then 
> > offsetof(HeapTupleHeaderData, t_bits) will be 32 and for
> > no-nulls tuples there will be no difference at all
> > (with/without additional 6 bytes), due to double alignment
> > of header. So, the choice is: new feature or more compact
> > (than current) header for tuples with nulls.
> 
> That's a tough one.  What do other DB's have for row overhead?
> 
Informix has a per page overhead of 36 bytes (per 4k or 2k page) 
+ 4 bytes per row and page
Data resides on: Home page, big remainder page, remainder page. 
no length or precision byte per column for fixed width/precision fields.
It has a maximum of 255 rows per page (4k page, 11 bytes min rowsize)

Andreas