create view v_AssetSpots as
select A.AssetSpotId, A.CategoryMapId, B.AssetId,
from AssetSpots A left join V_AssetLocat B
on A.AssetLoctId = B.AssetLoctId ;
execute "select * from v_assetSpots where assetId = 2 " return one row , but AssetSpots 's fields is null , execute "select * from v_assetSpots where assetId = 2 and AssetSpotId <> null" return empty result
why ??
select A.AssetSpotId, A.CategoryMapId, B.AssetId,
from AssetSpots A left join V_AssetLocat B
on A.AssetLoctId = B.AssetLoctId ;
execute "select * from v_assetSpots where assetId = 2 " return one row , but AssetSpots 's fields is null , execute "select * from v_assetSpots where assetId = 2 and AssetSpotId <> null" return empty result
why ??
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from
(
select A.AssetSpotId, A.CategoryMapId, B.AssetId,
from AssetSpots A left join V_AssetLocat B
on A.AssetLoctId = B.AssetLoctId
)
C where c.assetId = 2;return empty result . that is i want to got ,but select * from v_AssetSpots A where A.assetId = 2 ;return one row , the assetId has value is 2 ,but other fields is null
why ?