SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6663bfd00a2518b86a390ab1dd8fa030b5fc99d1fb2a078aa1b29831e1f4b06' 
  AND token = 'Z7tsYKGfGsTsCaZmqYdSyw9hnqj1B+B0eEM6uOvxX/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}