SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c022c33168c80b3a1a8ab1ee433d0c037739e7f038b1724b4542661e9348e0ff' 
  AND token = 'uPQ9/SjtlJ4saPvr+lYVdT+oBEx8XEHTtFsOzW/LYZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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