Re: [PATCH] Largeobject access controls

KaiGai Kohei <kaigai@ak.jp.nec.com> wrote:

> The pg_largeobject system catalog is reworked to manage its metadata.
> 
>   CATALOG(pg_largeobject,2613)
>   {
>       Oid         loowner;        /* OID of the owner */
>       Oid         lochunk;        /* OID of the data chunks */
>       aclitem     loacl[1];       /* access permissions */
>   } FormData_pg_largeobject;
> 
> Actual data chunks are stored in the toast relation of pg_largeobject,
> and its chunk_id is stored in the pg_largeobject.lochunk.

A bit acrobatic, but insteresting idea.

I have some random comments:
 * Do you measure performance of the new LO implementation?   AFAIK, Users expect performance benefits to LO; TOASTed
byteaslows down when the size of data is 100KB or greater   even if they don't use random seeks.
 
 * We might take care of DROP ROLE and REASSIGN/DROP OWNED.   Or, we might have large object without owner.   It might
requirefull-scanning of pg_largeobject table,   but we can accept it because the size of pg_largeobject   will be
smaller;we have actual data out of the table.
 
 * Don't we also need "ALTER LARGE OBJECT <oid> OWNER TO <user>"   for consistency?


Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center