The blockchain is a list of all transactions that have occurred using the Bitcoin currency. Please don't use this tag for the service named 'blockchain.info'.

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What if some group of people start sending small transactions from wallet to wallet just to make the blockchain bigger?

What if some government start using their computers to move the tiniest amount of Bitcoin possible, from wallet to wallet, just to make the blockchain REALLY big? Is this possible? And also, is it ...
3
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2answers
58 views

How often does a block have only one transaction?

I was looking at blocks on blockchain.info, and came across this one with only one transaction in it: (the mining reward one) ...
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2answers
60 views

Help me understand Bitcoin analytics

I'm trying to use the Blocktrail API to look at the oldest Bitcoin addresses to create a info graph piece - besides looking at historical transactions, what else would be good for me to analyze? \\ ...
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0answers
16 views

Armory can't find blockchain files produced by bitcoin-qt

Armory is telling me to restart the application using --satoshi-datadir=[path] But I don't understand how to do this? I'm running MacOSX. I know where the blockchain is. How do I start Armory with ...
0
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1answer
41 views

Lower confirmation time schemes: any requirement between confirmation time and the probability to find a block during that confirmation time?

Bitcoin, the first blockchain-based cryptocurrency, set a 10 minute confirmation interval time; LiteCoin set a 2 minute confirmation interval time; DogeCoin set it at 1 minute; QuarkCoin set it at 30 ...
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1answer
31 views

Safely interrupt -reindex?

My database became corrupted and I had to reindex: bitcoind --daemon -reindex It takes my computer quite some time and CPU power. It's been running for an hour but it will take at least 4 more ...
0
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1answer
39 views

My balance gets sent back to me [duplicate]

I'm using the blockchain API to make a "send to many transaction". In the recipients I only put other people addresses, but somehow the API sends the remainder of my balance back to me. For example: ...
1
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1answer
30 views

Query Blockchain: Reference previous transaction in “txin”

I'm currently working with a postgresql database I've downloaded here which has the following schema and has probably been parsed using Bitcoin-ABE (I added some indexes and redundant columns): Now ...
2
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1answer
39 views

What happens to off chain transactions when the blockchain is reorganised?

Many companies seem to use off chain transactions to transfer bitcoins between their own customers. What happens when a side chain gains dominance and no longer contains a block with the underlying ...
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1answer
62 views

Bitcoin 101, need some knowledge [closed]

I am new to bitcoin. How do I check if my blockchain is working? I have tested some free bitcoin sites but neither of them have worked.
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2answers
115 views

How to fork an Altcoin Which has 0 Reward Block to continue mining after the LAST POW BLOCK

Im trying to learn how is it possible to Hard Fork an Altcoin Blockchain to Continue the Mining Phase after the LAST POW BLOCK. The Block Reward is already 0 and the LAST POW stops at Block 8000. And ...
2
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2answers
114 views

Double Spending - Does each node maintain a list of unspent transaction references?

My Understanding Of How Bitcoin Prevents Double Spending Each transaction contains references to the input transactions and ever node has to verify all transactions from time immemorial to ensure ...
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0answers
42 views

Querying insight-api to dump all addresses with a positive balance

It's been some time I've been using 'insight-api' (https://github.com/bitpay/insight-api) and I couldn't find any documentation / anything helpful to query leveldb in a way that all addresses with a ...
2
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2answers
65 views

What methods are currently used to embed additional data into the Bitcoin blockchain?

Yes, I do understand that it is inappropriate to pollute the already large blockchain with data not necessary to make the currency work. But I know people are using Bitcoin as an underlying system for ...
1
vote
1answer
81 views

how to get one address from two public keys?

Parsing an input script of a transaction, I’ve come across two public keys in the script. Either public key is 33 byte long. I know how to transform a single 33 byte long public into an address. ...
1
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1answer
22 views

how to parse input script of a transaction in blkzzzz.dat file?

In data files, an input script of a transaction appears to be in this form: [funky byte 1][signature][funky byte 2][public key] Bitcoind displays an input script in this shape: [signature][blank ...
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0answers
39 views

Calculating Account Balance [duplicate]

Is anyone familiar with how the standard Bitcoin client gathers account balances from the blockchain? I understand that the software will look through the blockchain to calculate the balance, but I ...
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3answers
163 views

Blockchain programming books C#?

EDIT 1: It seems that what I really want to learn is how to create software which makes use of a distributed hash table. ORIGINAL QUESTION: I want to learn about coding my own blockchain based ...
3
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2answers
87 views

Why wait for several confirmations before shipping?

Suppose customers pay me bitcoins for their purchases. As far as I understand, I could check block chain that the proper payment amount has been made to the address I generate for each customer, and ...
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3answers
116 views

If using Bitcoin core client am I constantly going to be downloading data from the blockchain?

I understand you have to download the entire blockchain and sync in the beginning but don't you also have to constantly keep the software on if you want to buy/sell stuff, which means more data being ...
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2answers
74 views

When miners are working on their block, do everybody's block have the same transactions in them?

In this webpage https://en.bitcoin.it/wiki/Blocks, it says this "Bitcoin transactions are broadcast to the network by the sender, and all peers trying to solve blocks collect the transaction records ...
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0answers
26 views

Infinitecoin (IFC) transaction delay

A few weeks ago, I made a transaction from an online wallet (coins-e) to my personal (infinitecoin-qt) wallet. Initially I looked for the transaction ID using exploretheblocks for Infinitecoin's ...
2
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2answers
97 views

How can I create a list of X richest bitcoin addresses?

I have looked around, but I can't find the code related directly to my question. I want to create a list in any format that contains the all accounts with balance over 0 for example. Thanks ahead for ...
1
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1answer
67 views

How does a blockchain store any data?

I read here that since Bitcoin is a networked ledger, it is a good way to back up data. I would like to know two things: How does a blockchain store 'any' data? I would like to know more about a ...
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3answers
81 views

How are transactions broadcast to the rest of the network?

If a person sends a transaction to another person, and Bitcoin is a peer-to-peer application, how will the transaction get to the rest of the Bitcoin community? How does everyone have the same ...
0
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0answers
90 views

How to store 30kb file using Decentralized Blockchain Data Storage on NXT (nxtcoin) by attach messages?

I'm curious to how would one store a 30kb file on the NXT blockchain since the NXT protocol can attach a 1000byte message. My test scenario is storing a 30kb midi file on the nxt blockchain and then ...
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2answers
65 views

Block Chain API for BTC transactions

I want to fetch transactions for an address from the following api: https://blockchain.info/address/$btc_address?format=json The thing is understanding the json returned from the api, I don't ...
4
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1answer
78 views

What are 'pegged' side chains are and how they will be useful for Bitcoin?

What seems to be a very important paper was released this past week (http://www.blockstream.com/sidechains.pdf). It centers around the idea of 'pegged' side chains, and being able to move coins from ...
2
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1answer
47 views

Can side chains or “pegged” chains negatively affect the security of Bitcoin?

Regarding the concept of side chains or "pegged" chains which has been discussed since as early as 2011 and explored in this white paper, how can these negatively affect the security of Bitcoin? ...
2
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1answer
19 views

What does the main_chain value returned by blockchain.info mean?

What does it mean that for bitcoin block to be on the Main Chain? What other chains are there? Is this as opposed to testnet? This is regarding the main_chain value in the blockchain.info api here: ...
2
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1answer
43 views

How to exploit the possibilites of blockchain for proof of authorship?

I want to to create some kind of Proof-of-Authorship mechanism, that's something that many artists had asked before: How can I prove authorship of my work To accomplish my objective I need to deal ...
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0answers
22 views

If I want to run the Bitcoin client from another OS, can I direct Bitcoin to an already downloaded Blockchain on another OS' partition?

I have fast internet, and it wouldn't be too much of a struggle just torrenting the bootstrap.dat, but it would make sense to make use of an already existing blockchain and save space and time. I've ...
0
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1answer
41 views

Is it possible for corporate interests to incentivize securing alternate Blockchains instead of Bitcoin's Blockchain?

Is it possible for corporate interests to incentivize securing POW of alternate blockchains instead of Bitcoin's blockchain? Given the large amount of funding and/or "partnerships" announced the last ...
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1answer
31 views

How do I change the default blockchain Database download location for NXT?

I'm testing out the nxt client and was wondering how do i change the default database download location? Its currently downloading to the current folder (nxt_db).
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0answers
33 views

How fast is the NXT blockchain growing in 2014?

Is there a place that where I can find out how fast the NXT blockchian is growing? I'm curious because its this year (2014) where a bunch of nxt features came into the scene and was wondering how one ...
0
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0answers
105 views

Blockchain.info Wallet API: How can I send bitcoin without transaction fee

I am using Blockchain.info Wallet API for sending bitcoin. According to the API document, transaction fee must be greater than default fee. I tried to put the fee was 0 but the setting was ignored. ...
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1answer
31 views

Remove address from sequence in HD wallet

Is there a way to eject an address out of the sequence of an HD wallet? Lets say an address was used for a political donation to a regime in Namibia that may get international condemnation a few ...
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3answers
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Random numbers using blockchain

How are the block hashes generated? Are they trully 100% random (generated by hardware) or is it pseudo-random (generated by software)? Can i rely on it or any other blockchain data to make a 100% ...
0
votes
1answer
67 views

If all block chain copies get deleted, what would happen?

What would happen if all block chain copies get deleted at one time? At first, all clients would try to get the block chain from other clients, right? But this would fail. Would the "network" then ...
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2answers
98 views

Difference between a bitcoin wallet and the blockchain

As the title said, what is the difference between the bitcoin wallet and the bitcoin core, do i have to install both of them to work? Can I just have a bitcoin wallet?
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1answer
194 views

What is a soft fork?

When people talk about possible changes to how Bitcoin works they sometimes say a particular change can be implemented as a soft fork. What does that mean? How does this compare to a hard fork?
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2answers
73 views

Can decentralized blockchain technology like bitcoin be used to store medical information? [closed]

For example patients get private key, providers get public key?
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1answer
57 views

Blockchain transaction message length limit

When I perform a transaction on the blockchain, I can add a message to the transaction, which will then exist forever in the blockchain. Say for example I wanted to use the blockchain to store ...
6
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4answers
364 views

How to find a specific bitcoin address from all the addresses?

Recently, I found a site that show all the addresses in a huge list, divided in 904625697166532776746648320380374280100293470930272690489102837043110636675 pages. The site's link is ...
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2answers
52 views

How much binary data (bytes) could I put in a transaction and how?

I know that some people had put text, pdf and images in the blockchain. I wonder which are the limits in order to have a minimum "bytes/btc" value in regarding the blockchain as a permanent database. ...
0
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1answer
53 views

Blockchain Parser not working on blockchain generated in regtest mode using bitcoind. Any help?

Has anyone used this blockchain parser for Bitcoin https://code.google.com/p/blockchain/ ? http://codesuppository.blogspot.in/2014/01/a-command-line-interface-for-blockchain.html I tried to parse ...
0
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1answer
36 views

Bitcoin-qt and lost local blockchain files

For some reason I've lost all data in my .bitcoin directory except the wallet.dat file. Now bitcoin-qt shows 0 balance, and it's 5 years behind sync. Is this possible to restore coins in this case?
0
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1answer
39 views

Local Testnet3, where do the new coins get sent to?

I'm trying to setup a local testnet with multiple nodes. Currently I have three nodes, and their mining powers are almost the same. When I use listaccounts RPC call, all the wallets have 0 coins. ...
0
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1answer
23 views

Why do Bitcoin API services offer Block details?

I understand having APIs around addresses and transactions, but I'm less clear why I need to know what's happening with a Block(s). This is to confirm one's transactions? Might someone provide some ...
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1answer
47 views

Bitcoin testnet: “Bitcoin is downloading blocks…” and other problem

I'm trying to setup a local testnet with multiple nodes. Currently I have three nodes, and their mining powers are almost the same. Things have been quite ok so far, except some problems that I need ...