SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ec425ca3411d48a6a94f82766eec51ca82fcc5e6a9afbd1bcabaa26a928aef0' 
  AND token = 'QxVQbD6bLirK92BhC60IZTWOYvMg6utR7WfgDPcaZes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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