At 15:29 23/10/00 +0900, Hiroshi Inoue wrote:
>
>If we have a mechanism to acquire a share lock on a tuple,we
>could use it for managing system info generally. However the
>only allowed lock on a tuple is exclusive. Access(Share/Exclusive)
>Lock on tables would give us a restricted solution about pg_class
>tuples.
>
Don't we have this ability? What about taking a RowShare lock on the
pg_class tuple whenever you read from the table; then requiring schema
updates take a RowExclusive lock on the pg_class tuple?
As you say, it won't prevent deadlocks, but it seems like a reasonable
thing to do.
----------------------------------------------------------------
Philip Warner | __---_____
Albatross Consulting Pty. Ltd. |----/ - \
(A.B.N. 75 008 659 498) | /(@) ______---_
Tel: (+61) 0500 83 82 81 | _________ \
Fax: (+61) 0500 83 82 82 | ___________ |
Http://www.rhyme.com.au | / \| | --________--
PGP key available upon request, | /
and from pgp5.ai.mit.edu:11371 |/
