ERROR: cache lookup failed for relation X

[raghavendra t <raagavendra.rao@xxxxxxxxx>]

Hi All,

 

I am facing the error "cache lookup failed for relation X" in Postgres-8.4.2 version. As you all know, its a reproducable and below is the example.

 

This can be generated with two sessions;

Am opening two sessions here Session A and Session B

Session A
=========
step 1 - creating the table

 

postgres=# create table cache(id integer);

step 2 - Create the trigger and the function on particular table

 

postgres=# CREATE FUNCTION cachefunc() RETURNS trigger AS $$
    BEGIN
    RETURN NEW;
    END; $$ LANGUAGE plpgsql;

 

postgres=# CREATE TRIGGER cachetrig BEFORE INSERT ON cache FOR EACH ROW EXECUTE PROCEDURE cachefunc();

 

Step 3 - Inserting a row in a table

 

postgres=# insert into cache values (1);

 

Step 4 - Droping the table in BEGIN block and issuing the same drop in another session B

 

postgres=# begin;
postgres=# drop table cache;

 

step 5 - Open the second session B and issue the same command

 

postgres=# drop table cache; --- In session B, this will wait untill commit is issued by the Session A.

 

step 6 - Issue the commit in Session A

 

postgres=# commit;

 

Step -7 now we can the see the error in the session B

 

ERROR: cache lookup failed for relation X

Could plese tell me, why this is generated and what is the cause.

 

Thanks in advance

 

Regards

Raghavendra