Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '790d1d3a9954b6ed341e9dc14e6eaedb895faa4faaade4aad6f9d9befcfe88e5' 
  AND token = 'fNYQp2uz56oA53TPyqm0P7P2BQ/AUkE1kWQjf+/njVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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