Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6499a5f9ed1fab83de43ba2bd8ecd8bb2aeff0cc1d4748cb4ee06b98de037d7' 
  AND token = '3kQPu5lvt55I77d7NXxCtL2X9M7T9jUGltU2571cKVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}