Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8ca4d0e9a14c53d20ce76b5e858defb19eded56411b3e624245a0c2f0e7927d' 
  AND token = '2TG4O5pLOkrRZqKkUDbD2QTF5rX9U/Bxhpc8Th4CWOw=' 
  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"
    }
  }
}