问题
How to convert following SQL Server query which uses unpivot
to a HANA SQL query.
SELECT
p.CardName,
REPLACE(p.groupcode1, 'QryGroup', '') groupcode1,
ocqg.GroupName
FROM
ocrd
UNPIVOT
(value
FOR groupcode1 IN ([QryGroup1], [QryGroup2], [QryGroup3], [QryGroup4],
[QryGroup5], [QryGroup6], [QryGroup7], [QryGroup8],
[QryGroup9], [QryGroup10], [QryGroup11], [QryGroup12],
[QryGroup13], [QryGroup14], [QryGroup15],[QryGroup16],
[QryGroup17], [QryGroup18], [QryGroup19],[QryGroup20],
[QryGroup21], [QryGroup22], [QryGroup23],[QryGroup24],
[QryGroup25], [QryGroup26], [QryGroup27],[QryGroup28],
[QryGroup29], [QryGroup30], [QryGroup31],[QryGroup32],
[QryGroup33], [QryGroup34], [QryGroup35],[QryGroup36],
[QryGroup37], [QryGroup38], [QryGroup39],[QryGroup40],
[QryGroup41], [QryGroup42], [QryGroup43],[QryGroup44],
[QryGroup45], [QryGroup46], [QryGroup47],[QryGroup48],
[QryGroup49], [QryGroup50], [QryGroup51],[QryGroup52],
[QryGroup53], [QryGroup54], [QryGroup55],[QryGroup56],
[QryGroup57], [QryGroup58], [QryGroup59],[QryGroup60],
[QryGroup61], [QryGroup62], [QryGroup63],[QryGroup64])
) as p,
ocqg
WHERE
value = 'Y'
AND ocqg.GroupCode = REPLACE(p.groupcode1, 'QryGroup', '')
ORDER BY
p.CardCode
回答1:
I don't think Hana SQL supports lateral joins (the apply
keyword in SQL Server). One method is just union all
:
select og.*
from (select o.cardname, g.groupcode,
(case when g.groupcode = 1 then groupcode1
when g.groupcode = 2 then groupcode2
. . .
when g.groupcode = 64 then groupcode64
end) as groupname
from ocrd o cross join
(select 1 as groupcode from dummy union all
select 2 as groupcode from dummy union all
. . .
select 64 as groupcode from dummy
) g
) og
where og.groupname is not null;
来源:https://stackoverflow.com/questions/60912704/how-to-convert-sql-unpivot-query-to-hana-sql