Hello,

the SELECT at the end of the example below provides wrong NULL values as result for
the columns s2, s3 and s4.

Best regards

DROP TABLE IF EXISTS fact;
CREATE TABLE fact (
atc INT(11),
v1 INT(11)
)
ENGINE=Columnstore;

INSERT INTO fact VALUES
(1,11),
(2,22);

CREATE OR REPLACE VIEW v_fact_primary AS
SELECT
atc,
v1
FROM fact;

CREATE OR REPLACE VIEW v_fact_secondary AS
SELECT
atc,
v1,
CAST(0 AS UNSIGNED) AS v2 – without CAST one gets "the storage engine ... doesn't support Unknown REF item
FROM v_fact_primary;

SELECT
atc,
SUM(v1) AS sum1,
SUM(v2) AS sum2,
CAST(SUM(v1) AS CHAR(100)) AS s1,

CAST(SUM(v2) AS CHAR(100)) AS s2, – not working
CONVERT(SUM(v2),CHAR) AS s3, – not working
'' + SUM(v2) AS s4 – not working
FROM
v_fact_secondary
GROUP BY atc;