SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0193c2857d3830ba6213c6b27941f45a5bbbe89bbf7be6dd4106eaf489d335b3' 
  AND token = 'kNWXuSh4q548HJ2XyMlWNBV/4k+SZpwwLLmKLUWRooI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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