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1500 questions
29
votes
3 answers
What is msg.data?
Is msg.data equal to {from: addr1, data:something}?
How to handle the data 'something'?
when execution this code:
web3.eth.sendTransaction({from: ..., to: addressOfE, data: something});
how to read the "data: something " ?
For example: data:…
wakerch
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29
votes
3 answers
What is the exact "longest chain" rule implemented in the Ethereum "Homestead" protocol?
This paper from 2016 claims (in section 3.3.2, speaking about the actual Ethereum implementation as opposed to the specification) that:
although uncle blocks that are included in a block receive a reward, they do not count towards the total…
Jeff Coleman
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29
votes
2 answers
How many transactions can the network handle?
The voting on ethereum analysis by Dominik Schiener calculated that it would take 40 days to hold the UK general elections on the ethereum blockchain due to the transaction and gas limits.
I redid his math with some more current figures, here is…
q9f
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28
votes
2 answers
Why is my node synchronization stuck/extremely slow at block 2,306,843?
Using macOS 10.12.1 with Ethereum Wallet 0.8.7, nodes are connected but Sync doesn't even start. Stuck at block 2,306,843.
What can I do? Please keep in mind, I am neither a coder nor a tech geek.
Ramsroyal
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28
votes
1 answer
Child contract vs struct
Let`s say I need to store and manipulate collection of complex data in the smart contract. There maybe complex rules defining who and how can change an item. There maybe be several millions of items in the collection.
There are 2 ways how that…
Sergey Ilin
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28
votes
2 answers
What are the peer discovery mechanisms involved in Ethereum?
There are several implementations of Ethereum clients. How do these clients find each other? What are the algorithms and peer-to-peer protocols involved in this peer discovery process?
galahad
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28
votes
7 answers
Deploy contract from NodeJS using web3
I'm trying to create and deploy a smart contract through NodeJS using web3, but it is not working as I get a "web3.eth.contract.new is not a function". Here is my code:
var web3 = require('ethereum.js');
var solc =…
Daniel Catita
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28
votes
2 answers
Can I use the same private key for Ethereum and Bitcoin?
Both Bitcoin and Ethereum private keys are usually a 256-bit number, isn't it possible to use the same private key for both Bitcoin wallets and Ethereum accounts?
For instance, the Bitcoin wiki states:
In Bitcoin, a private key is usually a 256-bit…
q9f
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28
votes
7 answers
TypeError: Data location must be "memory" for parameter in function, but none was given
I have created the contract below using the online IDE Remix. the smart contract was fine until late last night when i got the following error for all functions(targeting the string data types especially):
TypeError: Data location must be "memory"…
Lonwabo Zaula
- 391
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- 3
28
votes
3 answers
What is the default ordering of transactions during mining?
I know that the yellow paper does not specify how transactions are to be ordered in a block and this is up to the miner to decide. But I am interested in how this is practically handled (I assume not calling some rand function to get ordering). This…
SCBuergel
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28
votes
3 answers
Difference between Ganache and Truffle
What is the difference between this two? I understand that Ganache is like a fake blockchain, but Truffle has that too ?
What are the limitations of each and under which circumstance we use either of them ?
drhanlau
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28
votes
3 answers
What is a Shard?
Proof of Stake brings new concepts to the Blockchain ecosystem. In the dictionary "Shard" is defined as "A broken piece or fragment, as of pottery or glass".
Jmiehau
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28
votes
3 answers
Are there any public/free nodes to connect a Dapp front end?
I have a small Dapp written in Meteor (client only) that reads some contract and account info from the blockchain. I can deploy my front-end code for free on meteor.com (or a variety of other places), but I still need a node to connect to.
Do I…
eterps
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28
votes
3 answers
What is the current DAG size? When do we expect to hit GPU limits?
I have two mining rigs running, one with 2GB GPUs and one with 8GB cards. Recently, the rig with the 2GB cards failed due to the inability to upload the DAG to the GPU.
What's the current DAG size for miners and when do we expect to hit GPU-relevant…
q9f
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- 47
- 156
- 395
28
votes
2 answers
Is it a good practice to log an event every time I throw in Solidity?
In Solidity (0.3.2) I am aware that there is no way to throw specific exceptions. (Everything is an invalid JUMP error.) It seems beneficial to have a way to log specific errors. Does it make sense to create an Error event to be fired before any…
Raine Revere
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