SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac3e3313b2979614b054fc36fe2f22747f7c21077c793980cb6071aed8c535c9' 
  AND token = 'OvIF/YEqgXNfM1VLf48K2ioBVcj4lA+mq2JZE85mmQ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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