> -----Original Message-----
> From: owner-pgsql-hackers@postgreSQL.org
> [mailto:owner-pgsql-hackers@postgreSQL.org]On Behalf Of Vadim Mikheev
> Sent: Wednesday, June 16, 1999 10:13 PM
> To: PostgreSQL Developers List
> Subject: [HACKERS] Savepoints...
>
>
> To have them I need to add tuple id (6 bytes) to heap tuple
> header. Are there objections? Though it's not good to increase
> tuple header size, subj is, imho, very nice feature...
>
> Implementation is , hm, "easy":
>
> - heap_insert/heap_delete/heap_replace/heap_mark4update will
> remember updated tid (and current command id) in relation cache
> and store previously updated tid (remembered in relation cache)
> in additional heap header tid;
> - lmgr will remember command id when lock was acquired;
Does this mean that many writing commands in a transaction
require many command id-s to remember ?
Regards.
Hiroshi Inoue
Inoue@tpf.co.jp