Output – Transaction with NULL address input

adminJanuary 18, 2024

I was reading this article on the Bitcoin wiki (https://en.bitcoin.it/wiki/From_address). I understand the concept of UTXO and that every input to a transaction is an output of the previous transaction. I also have a rough understanding of how ScriptSig and ScriptPubKey interact. The article states that “advanced transactions will probably beat most block explorers” and provides examples of some transactions, including:

54fabd73f1d20c980a0686bf0035078e07f69c58437e4d586fb29aa0bee9814f

For example, when I view this transaction on blockchain.com, the input shows as “unknown” and when I view the JSON for the transaction, the input address says “null”.

  "inputs": (
    
      "coinbase": false,
      "txid": "a60143eb3f8d3cd1f42cca874f35736186d67c488efd3c1b7214bbd74b310e0c",
      "output": 0,
      "sigscript": "483045022100d92e4b61452d91a473a43cde4b469a472467c0ba0cbd5ebba0834e4f4762810402204802b76b7783db57ac1f61d2992799810e173e91055938750815b6d8a675902e014f",
      "sequence": 4294967295,
      "pkscript": "76009f69905160a56b210378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71ad6c",
      "value": 9000000,
      "address": null,
      "witness": ()
    
  ),

We then looked at the TXID entered. a60143eb3f8d3cd1f42cca874f35736186d67c488efd3c1b7214bbd74b310e0c The output address is also “null”.

  "outputs": (
    
      "address": null,
      "pkscript": "76009f69905160a56b210378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71ad6c",
      "value": 9000000,
      "spent": true,
      "spender": 
        "txid": "54fabd73f1d20c980a0686bf0035078e07f69c58437e4d586fb29aa0bee9814f",
        "input": 0
      
    
  )

Can someone please explain what is going on here? And how do you create these “advanced transactions” that clearly defeat the block explorers mentioned in the article (what’s so special about breaking block explorers?)

I saw the question: Can I permanently stop transaction tracking using PUSHDATA/OP_RETURN? Answer to “non-standard” vout type But I don’t understand what this means.

Edit: I saw the “null” address as output in the context of OP_RETURN, but that address is not available, so I don’t understand how it can be used as input.

adminJanuary 18, 2024