SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c5c489a830b79701e4f68d90bed98645b5f8a136af37de5ad47d4ef1a1db59b' 
  AND token = 'cuUW8FD4tKrVJHtYYUGOYtk77dRE0z8scOs8kJojcqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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