Re: [HACKERS] FOREIGN KEY and shift/reduce

Hiroshi Inoue wrote:

> Nice.
> I tried a little.
>
> < session 1 >
> => create table ri1 (id int4 primary key);
>    NOTICE:  CREATE TABLE/PRIMARY KEY will create implicit
>    index 'ri1_pkey' for table 'ri1'
>    CREATE
> => insert into ri1 values (1);
>    INSERT 92940 1
> =>create table ri2 (id int4 references ri1 match full on delete restrict);
>    NOTICE:  CREATE TABLE will create implicit trigger(s) for
>    FOREIGN KEY check(s)
>    CREATE
> => begin;
>    BEGIN
> => delete from ri1 where id=1;
>    DELETE 1
>
> < session 2 >
> => insert into ri2 values (1);
>    INSERT 92960 1

Outch,

    I see the shared visibility conflict. So the CHECK constraint
    trigger must get an exclusive  lock  somehow  -  I  think  an
    internal "FOR UPDATE OF" can do it - will try.


Thanks, Jan

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