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1
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1answer
36 views

how a system based on a blockchain would deal with exponential growth of informations carried in it?

I was reading this article about the difference between a blockchain and centralized servers and a question came up to my mind: if I understand well the difference stands in the fact that in a ...
-1
votes
1answer
129 views

How to explore ripple ledger?

I'm running a ripple node on my own server, and try to conduct some analysis to the balance of all ripple accounts. Thus I need to synchronize the ledgers and analyse them. Currently, my server has ...
0
votes
1answer
88 views

What's raw undo data for?

I see block chain is stored basically four pieces of data that are maintained: blocks/blk*.dat: the actual Bitcoin blocks, in network format, dumped in raw on disk. They are only needed for ...
1
vote
2answers
40 views

what's CCoinsViewDB::GetHeadBlocks for?

I have google a lot, there exists little information, confused with the code comments Retrieve the range of blocks that may have been only partially written. If the database is in a consistent state,...
2
votes
0answers
208 views

How to delete last n blocks / roll back to specific block number in Bitcoin Core? (Like `monero-blockchain-import --pop-blocks n`)

I have Bitcoin Core's bitcoind running and synced in a VM. Now I want to clone the VM and run one of the various hard forks (such as Bitcoin Cash) in the clone. The plan is to roll back my copy of the ...
1
vote
1answer
203 views

How to save the bitcoin core (bitcoin-qt) database for later?

Say I've received some Bitcoin using the Bitcoin Core wallet on some linux machine. Say I'm done playing for now. So now I want to free some disk space by deleting the huge database from this machine ...
0
votes
1answer
147 views

BTC number of transactions

I'd like to get number of transaction's data with API. I already use API of blockchain.info. Dose someone know other API? I want to get number of transaction every a minutes(or less than ten minutes)....
1
vote
2answers
162 views

Bitcoin core database gone after error no more free disk space? How can I recover my bitcoins?

So I got myself into this situation. I have a Bitcoin core wallet, which was up to date and all the way synced. Two days ago I tried to start it up again but when I tried to shut my laptop down I had ...
8
votes
1answer
585 views

UXTO DB structure

After update Bitcoin Core to version 0.15, chainstate database changed format of data. Old prefix of key has been 0x63, now 0x43, and key/value are different Where is the new format described, or ...
0
votes
1answer
63 views

Building libbitcoin libraries on Arch linux fails

I'm trying to build libbitcoin libraries on Arch linux. First I tried to download AUR packages. I successfully installed libsecp256k1 and libbitcoin. But if I try to compile libbitcoin-system and ...
0
votes
1answer
103 views

Blockchain to store private data and ownership

As far as I know Bitcoin Blockchain can be accessed via API to enter data. In this case I want to generate a hash/ Checksum MD5, that cannot be understood by anyone that doesn't have the private key, ...
0
votes
1answer
77 views

Tool to build a relational db from .dat block files

No need to elaborate too much. I'd like to build a real SQL db starting from the directory blocks. Is there any tool out there? I work on a mac and I'd prefer something cross OS if possible.
3
votes
1answer
660 views

What database engine does Bitcoin and other top altcoins use?

I'm curious to what database engine does Bitcoin and other altcoins use to store their blockchain data. Do they all support sql queries or is it something else? The main ones I'd like to know are: ...
0
votes
1answer
3k views

To create a blockchain using MySQL database

I want to create local blockchain for my application. New blocks should be created while giving reference to previous block. But I am not getting exactly how will I do it in MySQL? I got some idea ...
1
vote
2answers
124 views

Bitcoin full database is not equal on each node

Is it true that a full bitcoin database is not equal on each node? I mean database (files) in blocks dir, which create official bitcoin client locally. What is that bitcoin database?
2
votes
1answer
89 views

Resyncing bcoin brings up database version error

I was resyncing my bcoin node and got the following error: Error: Warning: Your database does not match the current database version. This is likely because the database layout or serialization ...
3
votes
0answers
56 views

How does the new database design used by Bitcrust work?

I've recently learned about a new Bitcoin node implementation in Rust called Bitcrust. They state that they have found a novel way of storing the Bitcoin blockchain as a "Spend tree" instead of ...
1
vote
0answers
166 views

bitcoind verifychain vs reindex

actually this is not Bitcoin but Litecoin 0.13.2 on Linux Mint, litecoind stopped with "bus error" just on start verifying blocks: tail ~/.litecoin/debug.log ... 2017-05-06 21:15:26 Verifying last ...
0
votes
1answer
87 views

Where can I find historical exchange rate data for Dash (ex DarkCoin)/USD?

Is there a public data provider that allows to download the full history of Dash (ex DarkCoin) vs. US Dollar exchange rates?
0
votes
1answer
181 views

Chainstate database verification

When you download the blockchain, do you download the chainstate too or it has to be generated by your own machine (it says that theoretically can be rebuilt from the block data but it is time ...
0
votes
1answer
611 views

Is there any tool to extract the bitcoin transaction network from the blockchain?

I'm looking for a way to extract some data from the latest downloaded bitcoin blockchain. In particular I'm interested in extracting the whole transaction network, so input and output public keys used ...
15
votes
1answer
2k views

Migration from Berkeley DB to LevelDB

In 2013 a new bitcoin core was released and one of the supposed improvement was migrating from Berkeley DB to LevelDB. According to the release notes at bitcoin.org: LevelDB, a fast, open-source, ...
3
votes
1answer
383 views

Why are blk*.dat files ~134200000 bytes?

I understand that blocks are stored on disk across multiple blk*.dat files, but why is the maximum file size roughly 134,200,000 bytes? What's the reason behind this file size? Where can I find this ...
1
vote
0answers
158 views

What type of database does Bitcore use?

What type of database does Bitcore use to store the blockchain data? I can't find information on it. Does it use leveldb?
8
votes
1answer
2k views

Why is Bitcoin Core using LevelDB instead of Redis or SQLite?

Why did Core move from BDB to LevelDB? Why don't they use SQLite or move to Redis now? Is there a technical reason for this choice?
-1
votes
4answers
538 views

How to create a Database on Blockchain and retrieve it after applying some operation and constraints on the data of tables?

I want to create a database on Blockchain which gets input from a HTML form and add a tuple to table on Blockchain on each submission.The Tuples on Blockchain will be sorted by applying some ...
6
votes
1answer
7k views

Where can I learn how to build a blockchain from scratch?

I am a newby programmer, I am learning python and objective C and I want to learn how to build a blockchain from the beginning. Are there any resources that could help me.
4
votes
2answers
660 views

What is special about a private blockchain based on proof of stake?

I recently came across a paper published in 1988 called "A quorum-based commit and termination protocol for distributed database systems". I could not read it because it is not free, but to me this ...
3
votes
1answer
110 views

Access the NXT / Ardor database console?

I want to do some queries on the H2 database. How can I access this console that lets me type in commands.
3
votes
3answers
374 views

How long is a Bitcoin?

I searched already but I couldn't find anything about the structure of a bitcoin. My understanding is that a bitcoin, which is different AFAIK from a bitcoin address, can be interpreted as a string ...
5
votes
1answer
409 views

Why does bitcoind use a fork of LevelDB for key-value storage?

Since 0.8 bitcoind uses LevelDB for the storage of the UTXO set in chainstate/ and the block index in blocks/index/. On github special branch of LevelDB can be found: https://github.com/bitcoin/...
1
vote
1answer
227 views

storing bitcoin's database directory on an external drive?

I have a new-ish powerful laptop with SSD, limited to 128GB. It came with a RAID which somehow didn't work for installing linux, so I had to disable the RAID and now I have actually two 64GB disks ...
1
vote
1answer
559 views

Chainstate database for download

Is it possible to download a recent snapshot of the chainstate database? I'm running bitcoind (v. 0.11.8) on a machine with ~1mb/s download speed. After my client reached 300000 blocks, the ...
1
vote
0answers
56 views

name coin applicability to RDF data model URI specification

In the RDF data model things are named with URIs which are essentially just URLs with more precise information appended to them. See here: @prefix eric: <http://www.w3.org/People/EM/contact#>...
2
votes
2answers
450 views

Why are existing distributed database technologies not applicable to cryptocurrencies

Why are existing distribued database technologies such as mongodb not useful for hosting the blockchains of large cryptoapplications, after all they are just distributed key-value stores? how does ...
1
vote
0answers
86 views

Using Bitcoin with MEAN stack

I want to make a web app that accepts and uses Bitcoin, complete with user accounts, bitcoin storage per user, etc. How would I go about hooking this up using MEAN? Is there a reference for setting ...
29
votes
7answers
9k views

Is a private blockchain better in any sense than a database?

Since the banks appear to be currently looking into the idea of "blockchains" but don't want to be dealing with "Bitcoin", it seems that there is a lot of hype for private blockchains out there like ...
3
votes
1answer
628 views

Trying to understand how bitcore-node stores the data in the DB

I'm looking into the data and source of bitcore-node ( http://bitcore.io/ ), I'm a bit confused how all the information is stored in the database, probably it's in a similar way to others block ...
5
votes
3answers
5k views

Possible to speed up reindex?

I just reindexed a node that was already synced (in order to enable txindex); it took around 9 hours. It's on a pretty good system: 16G RAM, i7 with 4 physical cores. Storage is a weak point, with ...
6
votes
4answers
837 views

Blockchain as a way to host truly free social website like reddit

Some time ago I started wondering: what if we create a new coin and use its Blockchain to store a website content? Bitcoin is P2P, that way it is almost impossible to block bitcoin. Everything in the ...
1
vote
1answer
203 views

How to query bitcoin database created by Toshi?

I want to query Toshi's(https://github.com/coinbase/toshi) database but can't figure it out how to connect to it. It seems like it runs inside a docker container. Appreciate any help.
3
votes
1answer
492 views

What is the most efficient way to store bitcoin addresses in a database?

Let's pretend I wanted to store 1MILLION btc addresses in mysql, I thought about saving the last 10 digits of each submitted address and testing against that but would 10 characters be enough to ...
4
votes
3answers
497 views

Using Bitcoin or another Altcoin for Decentralized Database Storage

I was wondering has there been any attempts on using the blockchain as a decentralized database storage system? Would it be feasible to use it on Bitcoin or another Altcoin and if so which altcoin ...
1
vote
1answer
454 views

Bitcoin database needs to rebuild every time after defrag or reboot

I'm running Windows 10 technical preview 10049 and I'm running bitcoin-qt from my data hard drive with 1.17TB available disk space. It is a striped volume and due to much data writing and deleting it ...
2
votes
2answers
456 views

How does “headers first” effect BLKxxxx.dat structure?

Assuming a full node running Bitcoincore v0.10 (with txindex=1), how exactly does the new "headers first" functionality affect the structure of the blockchain data? (Specifically, the blkxxxx.dat data,...
1
vote
1answer
2k views

Error initializing block database. Do you want to rebuild the block database now?

I'm trying to set up a test network consisting of 3 nodes, each with different bitcoin.conf. I've constructed the directory and the .conf-files similar to what is the state of the art in qa/pull-...
4
votes
3answers
3k views

How to store blockchain data

If I wanted to imprint the blockchain data on a database, with the purpose of performing complex or just different than the RPC-based queries, how would I do it? Would I have to go for a relational ...
1
vote
1answer
337 views

how can I run multi wallet on one computer to share same blockdata

you know ,you need a 32GB size for one bitcoin client,is it possible to run several bitcoin programs sharing same data source using -datadir or something else? I have found that somebody had put it ...
1
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0answers
427 views

Bitcoin Historical Price API/Database

I have found many APIs and databases that exist for historical Bitcoin prices but they will only give you data for daily intervals or tick data. Is there an API / database that exists that will ...
3
votes
1answer
1k views

How can I read chainstate database?

1) What is the format of the LevelDB databases stored in the database directory? I know there are some custom blockchain parsing libraries, such as this one, but I'm wondering if I can just do a read ...