How to use Etherscan to check transactions on ethereum blockchain world

As buy and sell transactions are done on centralized CEX exchanges, the role of transaction tracking platforms like Etherscan is relatively small. However, with DeFi's tremendous growth, the need to use Etherscan to find out the technical problems of projects is extremely large. So what is Etherscan and how to use these block explorers? Let's find out through the article below.

How to use Etherscan to check transactions on ethereum blockchain world

About Block Explorer

Block Explorer is a platform that helps track all activities on the blockchain. Each blockchain network has a different explorer, for example Ethereum has Etherscan, and TRON has TronScan, Binance Smart Chain has BSCscan.

Okay, so the purpose of this browser is known, but how is it used? Firstly, we need to understand a few basic concepts that often appear on this platform.

  • Transaction Hash (or TxHash) : This is a transaction code, making it easy for the platform to track and retrieve, it's like an ID or identity card.
  • Status : This is the status of the transaction (including Success, Validation and Failure).
  • Block Height : This is the block number to which this transaction is attached.
  • Timestamp : The time when the aforementioned block was mined.
  • From : Transaction sender.
  • To : Transaction recipient.
  • Transaction fee : Transaction fee (in ETH), this amount is paid to miners.
  • Gas Limit : This is the limit of gas fees that you can accept, beyond this level, the transaction will automatically stop.
  • Gas Fee : the gas fee of the transaction that the user wants to pay.
  • Nonce : Transaction count. Initially this number will be 0 and will gradually increase to 1 unit after each transaction. The purpose of this indicator is to ensure that there is no double-spending (two transactions at the same time, when in fact the balance is minus one).

Types of transactions

That said, it's already lengthy, hopefully you won't find it too confusing and confusing. Now we will go through the transaction types section. There are three main types of transactions (a) between people (EOA – EOA), (b) the act of creating smart contracts by users and (c) between people and smart contracts.

Note: each user address is considered an EOA.

User send to user

We will come to an example of the first type of transaction – person to person (EOA – EOA). This is simply a transaction where Mr. A wants to transfer an amount of ETH to Mr. B. The reason we can distinguish this type of transaction is because the "Input Data" field is left blank.

What is Input Data will be explained in the second transaction form!!!

Transaction creates smart contract

Next is the type of user that creates a smart contract. At this point, Input Data will be the information that this creator wants to note about the smart contract. This information is bytecode, which is a string of symbols that looks complicated and sometimes “fears” many ordinary users – but it is actually complex and scary.

Usually, when projects issue tokens, they will have to create a smart contract using this transaction. When searching for a token to add to your wallet, you can also use the token's smart contract address to make searching easier. But make sure the address is correct.

Back to the smart contract creation transaction form, in the homepage section, we can track the creator's address, as well as the Hash (txHash) code of the transaction that created this contract.

Transfer ETH from outside to smart contract

Finally, when the user sends ETH from the outside into the smart contract. At that time, the user's request will be sent to the Global State (imagine it like the total network), from which the system will subtract their ETH balance and increase the smart contract's ETH balance.

We will have a variant, which is both a person-to-person transaction , but with a smart contract in the middle . This type of transaction is a transaction where user A transfers ERC-20 tokens to user B.

Unlike an ETH transfer , where the user will submit a request to the Global State, when an ERC-20 transaction, the user (ie EOA) will have to interact with the smart contract. Each token like UNI, SUSHI will have its own smart contract address, and when transferring these ERC-20 tokens, you are essentially asking the smart contract to deduct your balance and raise the recipient's balance.

From there, in the Input Data section, there will be information related to this smart contract. For example, the above sample transaction has a transfer function, ie transferring money from Mr. A to Mr. B.

That's it, we already have a rough grasp of the background knowledge about Etherscan. Now let's learn some basic examples to practice.

What is this transaction?

In case Fei Protocol, let's go through some transactions related to this project. The picture below is the "Overview" tab of the transaction, we will start to dissect each part based on the information mentioned in the previous sections.

At the top we have information such as the hash of the transaction, the successful status, the number of blocks and the time of execution. The From section tells us the sender's address. And because this is an interactive transaction between a person and a contract (3rd form), so in the "To" section we have the address of the contract to be interacted with.

Next we will have a Transaction Action section – this section will help explain the operations performed with the contract so that it is closer to humans, and the Token Transferred section is step-by-step to perform the above operations.

  • The first is to add liquidity to the Uniswap Pool. This pool is a FEI-ETH pair.
  • Next is adding FEI and TRIBE to Uniswap's liquidity pool.
  • The last step is to swap FEI with TRIBE on Uniswap.

Finally, below we will have information about transaction fees, as well as an Input Data section that shows the function that the creator used to interact with the contract - that is launch().

So, we have learned the most basic knowledge to be able to read and understand transactions on Etherscan, hopefully the above article is not too complicated, to help make DeFi closer to many investors.

Note: The above article is for informational purposes only and should not be considered investment advice.

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Sep 18, 2022

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