Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '51a3f74ffb2919f78ad81caee4bd51d4080de51e319b5d8254e3d07c95f6d843' 
  AND token = '4rUd2dVXk6NjUgZTIVmRP0YxEHA2jHZCps7vT4kWdpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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