why OEM recommended

I have the below query:

SELECT * FROM TEST
WHERE OBJECT_ID = :B2 AND :B1 >= DAYTIME AND :B1 < NVL(END_DATE,:B1 +1)



so when I run SQL tuning advisor, below is what OEM found:

The predicate NVL("TEST"."END_DATE",:B1+1)>:B2 used at line ID 1 of the execution plan contains an expression on indexed column "END_DATE". This expression prevents the optimizer from efficiently using indices on table "BLAH"."TEST".



question is

1. how OEM picked NVL("TEST"."END_DATE",:B1+1)>:B2
2. what does OEM really recommend to improve the query?

thx

It's your query, you tell us what you're trying to do.

Like it said, you are applying a function against an indexed column. If you want the use of an index, don't apply a function against it.