SQL error

Dear All,

I' m asking your opinion about the following behavior.

First SQL
The follow sql does not work. It's return SQL0122 error "Column *N or expression in select is not valid"

Select 'K' AS TIPO , 1 AS PERIODO , TTBACK CONCAT TTBDCK AS ELEMENTO1
, TTBPCK AS ELEMENTO2 , count(*) AS QUANTITA ,
IFNULL((Select COUNT(*) FROM SNVEI0F INNER JOIN IBM_DAT/SNCON0F
ON B5CSCK = BNCSCK INNER JOIN IBM_DAT/SNSLL0F ON B5BACK = IMBACK
and IMKDCK = 'DV1' INNER JOIN IBM_DAT/SNSLR0F ON
IMKDCK = N2KDCK and IMCCKK = N2CCKK WHERE B5BACK CONCAT
B5BDCK = TTBACK CONCAT TTBDCK AND B5BPCK = TTBPCK AND
B5CFDT <= 1230131 AND B5CWDT > 1230131 AND B5CFDT <> 0 AND B5BWST
IN ('D') AND B5JDST in (' ' , 'H') AND B5BACK IN ('A01')
) , 0) AS QUANTITAORDINI ,
0 AS QUANTITALIBERA FROM IBM_DAT/SNCID0F INNER JOIN
IBM_DAT/SNCON0F ON TTCSCK = BNCSCK INNER JOIN IBM_DAT/SNSLL0F
ON TTBACK = IMBACK and IMKDCK = 'DV1' INNER JOIN IBM_DAT/SNSLR0F
ON IMKDCK = N2KDCK and IMCCKK = N2CCKK WHERE TTH2DS >= 20230101
AND TTH2DS <= 20230131 AND TTBACK IN ('A01')
GROUP BY 'K', 1 , TTBACK CONCAT TTBDCK , TTBPCK

Second SQL
The follow sql work fine. It's the same of the previous without che concat expression in the last group by clause

Select 'K' AS TIPO , 1 AS PERIODO , TTBACK CONCAT TTBDCK AS ELEMENTO1
, TTBPCK AS ELEMENTO2 , count(*) AS QUANTITA ,
IFNULL((Select COUNT(*) FROM SNVEI0F INNER JOIN IBM_DAT/SNCON0F
ON B5CSCK = BNCSCK INNER JOIN IBM_DAT/SNSLL0F ON B5BACK = IMBACK
and IMKDCK = 'DV1' INNER JOIN IBM_DAT/SNSLR0F ON
IMKDCK = N2KDCK and IMCCKK = N2CCKK WHERE B5BACK CONCAT
B5BDCK = TTBACK CONCAT TTBDCK AND B5BPCK = TTBPCK AND
B5CFDT <= 1230131 AND B5CWDT > 1230131 AND B5CFDT <> 0 AND B5BWST
IN ('D') AND B5JDST in (' ' , 'H') AND B5BACK IN ('A01')
) , 0) AS QUANTITAORDINI ,
0 AS QUANTITALIBERA FROM IBM_DAT/SNCID0F INNER JOIN
IBM_DAT/SNCON0F ON TTCSCK = BNCSCK INNER JOIN IBM_DAT/SNSLL0F
ON TTBACK = IMBACK and IMKDCK = 'DV1' INNER JOIN IBM_DAT/SNSLR0F
ON IMKDCK = N2KDCK and IMCCKK = N2CCKK WHERE TTH2DS >= 20230101
AND TTH2DS <= 20230131 AND TTBACK IN ('A01')
GROUP BY 'K', 1 , TTBACK , TTBDCK , TTBPCK

Third SQL
The follow sql work fine. It's the same of the first without SUBQUERY in the select sentence with the CONCAT expression in the group by

Select 'K' AS TIPO , 1 AS PERIODO ,
TTBACK concat TTBDCK as
ELEMENTO1
, TTBPCK AS ELEMENTO2 , count(*) AS QUANTITA ,
0 AS QUANTITALIBERA FROM IBM_DAT/SNCID0F INNER JOIN
IBM_DAT/SNCON0F ON TTCSCK = BNCSCK INNER JOIN IBM_DAT/SNSLL0F
ON TTBACK = IMBACK and IMKDCK = 'DV1' INNER JOIN IBM_DAT/SNSLR0F
ON IMKDCK = N2KDCK and IMCCKK = N2CCKK WHERE TTH2DS >= 20230101
AND TTH2DS <= 20230131 AND TTBACK IN ('A01')
GROUP BY 'K', 1 , TTBACK concat TTBDCK , TTBPCK

Same problem if i use a substr expression

So it's seem that when i place a subquery in a select the group by clause can't contains any complex expression
Honestly i don't find nothing in google related this topic

Thanks

Basilio



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