SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b153a254c21387bd8695e49c787ef5d86551dd713a146892bf8fb486fd100069' 
  AND token = 'Gn9pOda/3dk/qFTUnHE8GqmY6+TZFJpOuBSrfx4nGCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}