INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10

With LOCK MODE WAIT, a query involving a correlated Collection
Subquery would wait on locked row if querying using equal sign
on exactly  one value in main table, yet ignore the lock waiting
if multiple values allowed.


Consider following case:

create table t2 (c1 integer --primary key
 ) extent size 8 lock mode row;
insert into t1 values (1);
insert into t1 values (2);
create table t1 (c1 integer --primary key
 ) extent size 8 lock mode row;
insert into t2 values (1);
insert into t2 values (2);


Now open a transaction and remove t1's second row:

begin work;
delete from t1 where c1=2;


In parallel session now try:

set lock mode to wait 4;
set isolation to committed read;

select (select c1 from t2 where c1=t1.c1) a, * from t1 where
t1.c1 = 2;

select (select c1 from t2 where c1=t1.c1) a, * from t1 where
t1.c1 in (1,2);
select (select c1 from t2 where c1=t1.c1) a, * from t1 where
t1.c1 = 1 or t1.c1 = 2;
select (select c1 from t2 where c1=t1.c1) a, * from t1 where
t1.c1 = 1 or t1.c1 = 1;
select (select c1 from t2 where c1=t1.c1) a, * from t1 where
t1.c1

****************************************************************
* USERS AFFECTED:                                              *
* Users of IDS prior to 12.10.xC13.                            *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* Not waiting on a lock with collection subquery and parent    *
* query's WHERE clause allowing multiple values.               *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************

keiner bekannt / siehe Local-Fix

Datum - Problem gemeldet    :
Datum - Problem geschlossen :
Datum - der letzten Änderung:

03.12.2018
26.09.2019
26.09.2019

12.10.xC13