Questions tagged [transaction-id]

The unique identifier of a transaction corresponding to the sha256d hash of the transaction.

Filter by
Sorted by
Tagged with
23 votes
1 answer
4k views

What is Transaction Malleability?

The Bitcoin exchange MtGox has stated in this press release that "transaction malleability" caused them to stop sending bitcoins. A recent question asked if it really is an issue. But what is ...
user avatar
12 votes
2 answers
724 views

How can I avoid transaction malleability consequences?

Please note that this question is NOT a duplicate of other questions regarding transaction-malleability. My question is regarding a following scenario, that could happen on an exchange that uses on-...
user avatar
  • 220
8 votes
1 answer
2k views

What happens when two txid's collide?

Let's suppose that I can create SHA256d collisions, and I use this ability to create two transactions that have the same hash, A and B. These transactions are not the same, but they hash to the same ...
user avatar
  • 28.7k
8 votes
2 answers
10k views

How do I calculate the txid of this raw transaction?

I'm trying to parse a bitcoin block using Python. I called getrawtransaction over JSON-RPC. I got this: ...
user avatar
6 votes
2 answers
355 views

What would be the fastest way to query for a certain txid to get its inputs?

I am working in an artistic/visualization project that analyses Bitcoin transactions. I have a Bitcore instance with insight API and from a Python script I query through the REST API so the queries ...
user avatar
  • 192
5 votes
1 answer
550 views

Duplicated hash values in mining reward

This transaction is contained in two MainChain-Blocks: https://blockchain.info/tx/e3bf3d07d4b0375638d5f1db5255fe07ba2c4cb067cd81b84ee974b6585fb468 On Blockexplorer there is a note of this anomaly: ...
user avatar
5 votes
1 answer
438 views

SegWit and previous hash: txid or wtxid, or either?

With segwit there will be two transaction ids wtxid and txid Can either one of them be used as previous hash or only txid?
user avatar
  • 1,530
5 votes
2 answers
337 views

Why didn't Bitcoin implement segwit in the first place?

Why didn't Bitcoin implement segwit in the first place? Why and how does non-segwit Bitcoin enable a miner to change a transaction's txid? From Mastering Bitcoin ch. 7 § "Transaction identifiers": ...
user avatar
  • 4,307
4 votes
3 answers
2k views

Duplicate tx ids

Is there a quick and dirty way to detect all transactions whose tx-id can be found in more than one transaction since the genesis block? I would also like to see mutated transactions as well ...
user avatar
  • 1,366
4 votes
1 answer
1k views

How to compute SegWit txid?

BIP141 says wtxid is SHA256 of [nVersion][marker][flag][txins][txouts][witness][nLockTime]. Is data that hashed as txid includes witness? And will txid be presented in block, e.g. be counted when ...
user avatar
  • 91
4 votes
1 answer
2k views

Pairing pattern of txids in merkle tree

For constructing the merkle tree txids are paired and hashed. ¹ But how are these txids paired? Does it happen chronologically or is there a certain pattern of pairing?
user avatar
4 votes
2 answers
515 views

Why does txID generation consider signatures?

I've been reading a lot about transaction malleability, and noticed that the only way to achieve it is by altering the transaction signature/s. Why does the protocol even consider the signature in ...
user avatar
  • 61
4 votes
1 answer
3k views

Compute TxID of Bitcoin Transaction

Originally posted to StackOverflow but with no response. Thought I might have better luck here. I've successfully created a Bitcoin transaction in C# according to the protocol specifications. Here's ...
user avatar
3 votes
1 answer
3k views

What is the transaction ID?

I have sent a Bitcoin amount to someone who wants the transaction ID. What is this? Is it the hash shown on the LHS of the transaction?
user avatar
  • 31
3 votes
1 answer
90 views

Question about identical txids/merkle tree in Developer guide

I am new to the technical details about Bitcoin and has been reading Developer guide on bitcoin.org. I have a question about below contents mentioning merkle tree, identical txids. I googled and ...
user avatar
3 votes
1 answer
392 views

How are transaction IDs generated and how are they then changed by transaction malleability?

How are the transaction IDs generated for a Bitcoin transaction? How can the transaction ID change due to a transaction malleability attack?
user avatar
  • 264
3 votes
1 answer
147 views

By whom and when can transaction malleability be applied?

Once I create a transaction and relay it to the network, who can alter the transaction id? Can the transaction id change at any time or only when the transaction is confirmed or unconfirmed?
user avatar
  • 1,366
2 votes
1 answer
881 views

Duplicate transactions in blockchain

Can someone explain what does this mean: As i see: 2 transactions are having SAME txid and differ just by address. Is this normal behavior? Should I get both transactions in such cases?
user avatar
  • 207
2 votes
1 answer
2k views

Are transaction ids always the same length?

Do all bitcoin transaction ids (hashes) have the same length? I guess it's defined somewhere here: https://en.bitcoin.it/wiki/Protocol_specification but still I couldn't find it.
user avatar
  • 1,366
2 votes
1 answer
356 views

How to calculate txid for segwit transactions?

I'm having difficulty calculating txid for recent transactions. I followed bip-141 at https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki For the first transaction in the first block found ...
user avatar
  • 67
2 votes
1 answer
83 views

What is the impact of purposely sending a signed message with zero fee?

Would it be appropriate use of me to send a message with 0 fee on purpose if I have no need for the message to remain on the blockchain after it is seen by the recipient? I could sign a transaction ...
user avatar
2 votes
1 answer
227 views

Ripple: How to calculate transaction ID (TXID) [closed]

Given a signed Ripple transaction, how do I calculate the txid?
user avatar
2 votes
1 answer
752 views

Create raw transaction what txid

I want to check for every transaction if there is enough balance to pay it(including fee). I found this question: Is there a way to know the Bitcoin Network transaction fee BEFORE actually submitting ...
user avatar
  • 299
2 votes
1 answer
2k views

Figure out transaction ID

How can I find out the ID of a transaction I just made? I sent bitcoin to a site and they are requesting me to send the transaction ID to them. How do I find it out?
user avatar
  • 21
2 votes
1 answer
184 views

Refer to UTXO by output index or output full address in blockchain?

I'm writing my own simple crypto and wondering whether input in a transaction should refer to unspend output only by it's TXID and vout (index in outputs vector in a transaction) OR by it's TXID and ...
user avatar
  • 21
2 votes
1 answer
4k views

How to find a block containing a transaction using transaction hash only?

Well, the title says it all. I have a transaction hash and I want to find this transaction in the blockchain. I am working with bitcoinj. I am probably missing something very obvious here, but I ...
user avatar
  • 131
2 votes
1 answer
143 views

Alternative chain shows blocks with empty TXIDs - what's going on?

An alternative chain based on Litecoin 0.8.6.1 that I have an interest in is during certain low-difficulty periods showing several blocks that contain empty TXIDs. Digging into the TXIDs return ...
user avatar
1 vote
2 answers
196 views

Is txid a required field on all transactions?

I am writing a script that relies on txid to perform some tasks. I was wondering if it is possible for the txid to be missing from a transaction.
user avatar
1 vote
2 answers
43 views

How are TXIDs determined from the raw hex data of a block? Also, what is the coinbase transaction?

Consider the hex data of block 170. The coinbase TXID is this: b1fea52486ce0c62bb442b530a3f0132b826c74e473d1f2c220bfa78111c5082 and the second TXID is: ...
user avatar
  • 113
1 vote
1 answer
45 views

How does a node get information from the TxID?

If I'm right, segwit TxIDs are composed of the SHA^2(256) hash of the non-segwit data of a transaction. But, how does another node use the TxID to obtain information about the transaction such as the ...
user avatar
  • 113
1 vote
3 answers
825 views

Getting the wrong txid for coinbase transactions

I'm trying to hash transactions to get the txid. I get the hex values from blockchain.info. I get the correct hash for all transactions except for the coinbase when I hash it twice. Is there something ...
user avatar
1 vote
2 answers
240 views

Sending funds on same block of received funds. Confirm sending not received?

My question in quite conceptual: For creating a raw transaction, I just need the txid from the older transaction and the address to send it. Put the funds, the change, what's left is the fee. Sign it ...
user avatar
1 vote
1 answer
71 views

Bitcoin transaction not confirmed since 3 days ago [duplicate]

Hello I might sound stupid but it’s been three days since I issued bitcoin transactions, all unconfirmed so far. I use Blockchain.com to manage my wallet and have done everything normally (I think, as ...
user avatar
  • 11
1 vote
1 answer
499 views

How does TXID gets created and at which point

I see TxID in bitcoin transaction input as reference of the UTXO. How does TXID gets created and at which point, wallet or node?
user avatar
  • 21
1 vote
1 answer
169 views

Why does bitcoin-cli not show the correct TXID for this transaction?

I've been decoding some transactions on Testnet, and I've found one that bitcoin-cli decoderawtransaction seems to "fail" to decode correctly. Here's the TXID: ...
user avatar
  • 2,808
1 vote
1 answer
1k views

Unconfirmed BTC transaction / TXID doesn't exist?

I recently tried sending some btc to coinbase. In a hurry I did not put a transaction fee. I've tried to explain to their customer support what is going on. I offered to charge me a fee through my ...
user avatar
  • 61
1 vote
0 answers
27 views

Minimum characters to uniquely identify bitcoin trasanction in blockchain

What is the minimum number of characters (TXID from the beginning) which is generally considered to uniquely identify a bitcoin transaction in the blockchain? (Similarly to git and a commit SHA - ...
user avatar
  • 11
1 vote
0 answers
261 views

When computing a normalized transaction id, when do I finalize the sha256 hash?

I'm trying to compute the normalized transaction ID so that it matches what is on blockchain.into at the following URL http://blockchain.info/q/hashtontxid/ --- normal TX ID here ---- Given that I ...
user avatar
1 vote
1 answer
301 views

how can i get rid of a zombie channel in LND?

My LN-Node: 023bf99414b3e93ab7463ce60f44cd691f8be3c1ae33a2015fe784c85c36e770cf bitcoind 0.17.1 // LND 0.5.2-beta commit=v0.5.2-beta-rc7 Channel: 598078250466476032 Problem: lncli feereport returns: ...
user avatar
0 votes
1 answer
44 views

Developing a Bitcoin POS (Payment Page) - How do I identify the transaction

This is probably a basic question but I can not find an answer. We are developing a BTC payment process for a Point-of-Sale. We have managed to build this fine and can make requests (QR code) for a ...
user avatar
  • 103
0 votes
1 answer
582 views

Values for txid and vout for create a coinbase transaction

I want create a coinbase transaction to go with a new block minned by my program. I am creating it with the json-rpc command createrawtransaction. What's the values for txid and vout in this case?
user avatar
0 votes
1 answer
59 views

Is it only out of sheer luck that all my "txid"s are unique? How should I handle multi-vout transactions?

I have created a database table simply copying the information from listsinceblock from Bitcoin Core's API. I have a UNIQUE constraint set to "txid + vout", as I'm supposed to. But when, as ...
user avatar
0 votes
2 answers
1k views

getting address from public of ScriptPubKey vs ScriptSig

Recently I read some articles about BITCOIN protocol and it's transaction. I understand(maybe it is incorrect) these rules: An input is what we call an output when you're spending it in a transaction....
user avatar
  • 125
0 votes
1 answer
634 views

Find message attached to Bitcoin transaction?

Given a txid, can I find out the message/comment the transaction was attached with by the sender?
user avatar
0 votes
1 answer
441 views

Confused About Hash In Satoshi Nakamoto Diagram

In Satoshi Nakamoto's diagram: Consider the Hash block in the first transaction block above: How is that Hash value calculated? I see arrows from an Owner's Public Key and another arrow, so it's ...
user avatar
  • 357
0 votes
1 answer
86 views

tx-malleability who re-signed the tx?

It would be really great if there was a way to loop through all the txids in a new block and be able to check if you (can) sign your original transaction the same way it was re-signed - that it ...
user avatar
0 votes
2 answers
771 views

How to find out if LND opening pending channels has a confirmation onchain?

After typing lncli pendingchannels I get a channel_point number, and when I put channel_point txid to check if it was confirmed onchain by typing: bitcoin-cli gettransaction "txid insert" I get an ...
user avatar
  • 51
0 votes
1 answer
220 views

SPV clients querying the full node

Is there a way currently where an SPV client can send a TxID to a full node which is present in the UTXO set of the full node and have the full node not scan its entire blockchain to fetch the ...
user avatar
  • 13
0 votes
1 answer
328 views

Getting transaction id from raw transaction of a multisig address

I am able to get the tx id (or transaction hash) of almost any transaction but the one where the script starts with an "OP_O" (which is, I think, the null dummy introduced here https://github.com/...
user avatar
  • 59
0 votes
1 answer
116 views

What does postfic in the wallet transaction id mean

It's known the txid is always a 32 byte hex sequence for example ceca9c54d1a2f9122326a871a3b0b20b725540137e80cb50da663a404f7849a8, but when inpecting the transaction in a wallet it shows it with a ...
user avatar
  • 113