I am trying to write a query to calculate total transaction fees paid in USD. For that I am writing the below query but somehow join messes things up. ...

I want to build a smart contract function, which use caller's password as params. I have no knowledge about blockchain security, so I ask the followin ...

Below is a simple programme which includes web3 :- When I used the .size directly in Line 3 it is not showing the size of block. I checked the type ...

I am completely new to this blockchain world so I want to try learn it. While I am following a tutorial to create a simple ERC-1155 contract to mint a ...

Can anyone Explain me how uint variable accept address in this smart contract // SPDX-License-Identifier: Apache-2.0. pragma solidity ^0.6.12; libra ...

Here is my code, I have also added the options as well in the approve function which contains the from, to, gasLimit but that also doesn't work for me ...

I'm learning how the Uniswapv2 contracts work but I can't seem to wrap my mind around the swap() function. Reference: https://github.com/Uniswap/v2-c ...

I am planning out a new project in which I need to connect one particular Fiat payment gateway to my smart contract. I don't want to have a system wit ...

While attempting to fund me contract is tell me it encountered an error without specifying the error. I attempted to fund 0.1 eth through the fund fun ...

I tried to deploy following smart contracts but it fails with following message: The transaction has been reverted to the initial state. Note: ...

Is there a way to retrieve the most recent added/deployed smart contracts to the ethereum chain? Thanks a lot for any advice. Regards, JR ...

I have generated a private-public key pair using the web3j library. This returns an uncompressed form of the public key. I wanted to convert the sa ...

When I'm learning OpenZeppelin, I found its Ownable library has a function transferOwnership, which can give the owner of current contract to an addre ...

I'm learning solidity by official docs, one thing I'm not sure is that the address payable concept is only for contract address? Since I think the acc ...

I want to synchronize all transactions with the database, so I use get_ Block method. The code is as follows： but When I get all the transactions i ...

I'm trying to read total supply from this smart contract, I have checked the ABI and the read does not require arguments. Why am I getting this error? ...

Im a beginner in the blockchain/crypto world and I was wondering if there is a way to get the value of a crypto in another one on uniswap (like in the ...

I want to make connection to metamask and get the account balance : At runtime I get console errors : Uncaught ReferenceError: balance is not defin ...

This code runs successfully, and is able to add the data in the mapping. But, this does not change the size in the T1 contract. Is there any way i c ...

I am implementing a token that takes fees on buy/sell but not on transfer. I rely on checking the 'from' and 'to' for being uniswap pairs (V2 or V3) t ...