1. If you want to query the transaction records on the main network, you can use Etherscan. However, if you build your own private chain, how should you query the transaction records
the answer is that you need to listen to the logs on the chain, save them in the database, and then query them in the database. For example:
< pre t = "code" L = "Java" > varaddr = & quot& quot;< br />varfilter=web3.eth.filter({fromB lock:0 ,toBlock:' latest', address:addr });< br />filter.get(function(err,transactions){
transactions.forEach(function(tx){
vartxInfo=web3.eth.getTransaction(tx.transactionHash);
/ / at this time, the transaction information txinfo can be stored in the database
})< br />});
Web3. Eth. Filter() is used to monitor the log on the chain, and Web3. Eth. Gettransaction() is used to extract the information of the specified transaction. Once the transaction information is obtained, it can be stored in the database for query
recommend a practical introction, you can see: Ethereum tutorial
2. With bitpie wallet, this is the largest
bitcoin wallet in China. It can buy and sell bitcoin with one click, which is much more convenient than the exchange.
3. You can go to the major exchanges to buy it, but ordinary people still don't worry about it. They can't afford it at all. Even if they can buy it, they can't afford the unpredictable losses. But in the domain Kingdom, it's different. Investors can open an account with only $100, and they can make profits as long as they judge the rise and fall direction of Ethereum's price.
4. Note that Ethereum is 2.0 now. As of 13:57 on the 4th, the current deposit contract address of Ethereum 2.0 has received 1000098eth, and 31252 addresses have completed the mortgage of 32eth. With the increasing number of mortgage, the annual yield of mortgage will graally decrease. After the mortgage amount reaches 1 million eth, the current annualized yield is about 15.7%. Zhongyuan, a well-known exchange, has taken the lead in opening the
mining channel of eth2.0 verification node, and then launched qeth. Users can invest their own eth in verification node mining and exchange qeth to obtain liquidity, and then participate in mining. Compared with the disadvantages of eth2.0, qeth has too many things: the liquidity is guaranteed, the user does not have to bear the technical cost, the threshold of participation does not need 32 eth as low as 0.1eth, the nodes are maintained by the platform, and the income is distributed according to eth2.0.
5. The core component is the graphics card, which accounts for about 80% of the cost, followed by the motherboard and power supply, with high configuration. If you're digging deep in the mountains with a large mining machine. If personal computers are not enough for electricity, you can also choose crowdfunding mining machine... And now mining is generally in the place where electricity is cheaper, and the money is usually directly linked to the platform (currency exchange trading platform). Personal suggestions should be considered. After all, electricity is not enough.
6. It seems that there will be step prompts on the platform. When registering the domain Kingdom, just follow the prompts directly. It's not difficult.
7. -
register a digital currency wallet, which can be used to store the digital currency of your transaction
-
register an account number on the currency exchange, where you can trade many types of digital currencies, such as bitcoin, Ethereum, EOS, etc
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digital currency trading platform "currency exchange"
8. Ethereum specifies the JSON RPC API application development interface that each node needs to implement. This interface is transport independent. Applications can use this interface protocol to operate Ethereum nodes through HTTP, websocket or IPC and other communication mechanisms:
9. Some computers specialized in mining
virtual currency, such as bitcoin, need a lot of power supply, commonly known as mining power supply. The MOS tubes used in it are very high current and power consuming
at present, bitcoin trading is prohibited by the state, so those computers and corresponding accessories must be consumed in other places. Hehe, you can cut him three times to make him cheaper.
