SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00ab162bf94518732a901c6638177d3a9c8d86208019cb80285af5a57876f0a3' 
  AND token = 'c8sBh1VXRQxEhPE8sVmOfYB67jOv40lK25wPUBs59b8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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