SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7030b7d32fe8fc4db139c0b52ac09d228383687a335a8f7353aaf626debc998f' 
  AND token = 'fhDNCD1Y6znk4J9kXrIjAkuUKUGhXRPf4geyYhpZi8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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