Queries with IN lists whose accumulative length exceeds the length limit for IN lists may run out of memory

Detail name	Value
Changelog Number	4752
Type	Bug
Status	Resolved
Affected Versions	EXASOL 6.0.0, EXASolution 5.0.0
Fix Versions	EXASOL 6.0.5
Resolution Date	2018-07-25

Background
Queries may run out of memory if they contain very long IN-lists.
For instance

select * from t where t.x in ('1','2','3','4','5', ...., '1000000');

may run out of memory.
Therefore, EXASOL limits the length of IN lists with a default limit of 200000 elements.

Problem
The size limit is done per IN-list in a query.
Thus, when a query contains several IN lists whose sizes together exceed the limit, the query may still run out of memory

Proposed fix
Change the accounting of the IN list size limits such that it is global for all IN lists in a query.

Workaround
There is no workaround: The IN lists must be shortened or be replaced by subselects.
In the future instead of running out of memory, the SQL process will throw an exception and refuse to process such queries