SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3a07911f15a05026433bd514e10c673739869556c26e3261758d4db03cdfa3b' 
  AND token = 'NDQiCewvHEhXohc6R0ceVqv9Vu/rtbN4DwjKHqvCOJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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