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.
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