SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '181ca1ea9647689e02b1e7c2768cf6ba4d77b38bcaef619a93b085f24d40f67f' 
  AND token = 'tQZgz2uV0iNnZJTJiYOGnBWqtyG4QYWzlPsVMtUiU6k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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