Grouping set NULL results in data exception being raised for DATE and TIMESTAMP data types.

Detail name	Value
Changelog Number	21741
Type	Bug
Status	Resolved
Affected Versions	Exasol 8.25.0
Fix Versions	Exasol 8.29.10, Exasol 2025.1.0
Resolution Date	2025-05-15

Description

ROLLUP creates a hierarchy of grouping sets, including a final grand total grouping set (see also SELECT). Grouping set may include NULL.

In case of NULL value for DATE and TIMESTAMP data type, data exception like

SELECT c
FROM VALUES NOW() t(c)
WHERE FALSE
GROUP BY ROLLUP( c )
;

Error: [22008] data exception - invalid date value: year: 5000, month: 7, day: 0

is triggered. This is not expected.

Workaround

Cast the column to VARCHAR and back, like

SELECT CAST(c as TIMESTAMP)
FROM VALUES cast(NOW() as VARCHAR(100)) t(c)
WHERE FALSE
GROUP BY ROLLUP( c )
;

Fix

Works as expected.