Computed entity attribute without real table column

[AntonIV8]

Hello. I have simple table

LockKey: string (PK)
UserName: string
LockDate: Date

But the request looks like this:

SELECT PRIMARYKEY, UserName, LockDate, LockKey FROM public.____ WHERE (PRIMARYKEY = _____)

And get error, because primaryKey is not exist. But primary key must be like a calculating field, and work with real PK field "LockKey"

I try many JPA tricks, in particular variants of composite pk, but it doesn't work. Should entity attribute and column must be only hard ?