SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '431a1ece7ab9643de15abdfbb7b95d37984488edaab0c2a06946cfa6524206b0' 
  AND token = 'OjfPovsMm0KEN03SM6CCWbskm2ibJUmNrrA76PSAUlY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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