Select-List-Correlation with DISTINCT returns error

Detail name	Value
Changelog Number	12394
Type	Bug
Status	Open
Affected Versions	Exasol 7.1.0, Exasol 7.0.3, Exasol 8.0.0, Exasol 8.29.0, Exasol 2025.1.0, Exasol 2025.2.0

Description

A query with a correlation in the select-list in combination with DISTINCT returns the error message 'Feature not supported: this kind of correlated subselect'.

Example

SELECT distinct
  t1.c12,
  (SELECT 1 FROM tab_corr S WHERE S.corr_col = t1.c11 and S.corr_filter = 'text' ) -- correlation in select-list
FROM t1;

Workaround

Move the DISTINCT to an outer select

SELECT distinct *
FROM
(
  SELECT
    t1.c12,
    (SELECT 1 FROM tab_corr S WHERE S.corr_col = t1.c11 and S.corr_filter = 'text' )
  FROM t1
);

Fix

The query works without exception.