SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '391cbda32edc1677db22567addf8d9cfc0d3844473d4627c8d4537a27097f0ee' 
  AND token = 'lEenIPyp8Z6vC3z/IIgS7BlARzIXvYROUkIZC4BWzg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}