The oracle query statement always adds a where clause that is not part of the linq query.
It always inserts ("Extent1".THROUGH_DATE IS NOT NULL).
There is nothing special in the edmx for this table. Other table seem fine.
ex:
1.) DONATION.Where(c => c.THROUGH_DATE == null)
dbmon:
Execute: SELECT
1 AS C1,
............ deleted to be brief
FROM VCL.DONATION "Extent1"
WHERE ("Extent1".THROUGH_DATE IS NOT NULL) AND ("Extent1".THROUGH_DATE IS NULL)
2.) DONATION.Where(c => c.DELETE_USERNAME == null)
dbmon:
Execute: SELECT
1 AS C1,
............ deleted to be brief
FROM VCL.DONATION "Extent1"
WHERE ("Extent1".THROUGH_DATE IS NOT NULL) AND ("Extent1".DELETE_USERNAME IS NULL)
3.) DONATION.Where(c => c.BUCKET_NUMBER == null)
dbmon:
Execute: SELECT
1 AS C1,
............ deleted to be brief
FROM VCL.DONATION "Extent1"
WHERE ("Extent1".THROUGH_DATE IS NOT NULL) AND ("Extent1".BUCKET_NUMBER IS NULL)