readme.md

WTF Solidity Simplified Introduction - Tool 5: Using Dune for Visualizing Blockchain Data

Recently, I've been relearning Solidity to reinforce the details and write a "WTF Solidity Simplified Introduction" for beginners. I will update it with 1-3 lessons per week.

Feel free to follow me on Twitter: @0xAA_Science

Join the WTF Tech Community Discord, where you can find instructions to join the WeChat group: Link

All the code and tutorials are open source on GitHub: github.com/AmazingAng/WTF-Solidity

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What is Dune?

Dune is a blockchain query and analysis tool that allows you to query all the information on the blockchain using a SQL-like language, such as whale data, on-chain transaction data, and more. Additionally, Dune can easily convert data into visual charts.

Ethereum is a database, smart contracts are tables, and transactions from wallets are rows in each table.

This statement captures the essence of blockchain: it is essentially a publicly accessible distributed ledger for storing data, and now we can use Dune to query this distributed ledger.

Dune Official Website

First Query

Goal: Query the amount of DAI stablecoin purchased on Uniswap in the past 24 hours

1. Register and log in to Dune.

2. Click on new query in the top right corner to create a new query and enter the following code:

   SELECT
   SUM(token_a_amount) AS dai_bought
   FROM
   dex."trades"
   WHERE
   block_time > now() - interval '24 hours'
   AND token_a_symbol = 'DAI'
   AND project = 'Uniswap';

3. Click on Run in the bottom right corner to execute the query and get the amount of DAI purchased through Uniswap in the last 24 hours.

Building a Query from Scratch

Goal: Learn how to use SELECT, WHERE, and LIMIT

Let's query one of the tables, using Aave as an example: Aave Contract

By querying the Aave contract, we can see that it has a deposit method (for storing) and an associated event (which is broadcasted when executed).

Go back to Dune and search for the corresponding table by searching for Aave-related tables on Ethereum and matching the event, LendingPool_evt_Deposit.

Learning: SELECT, LIMIT, and WHERE to Query Data

Now we can query the corresponding stored data using Dune.

SELECT * FROM aave."LendingPool_evt_Deposit"
limit 100

This will give us the corresponding data for the storage method in the Aave contract. With this data, we can apply some filters.

Meaning of Each Field

_user: The wallet address that initiated the deposit.

_reserve: The token address used as collateral.

_amount: The amount of tokens deposited.

_timestamp: The timestamp when the transaction was mined on the blockchain.

Filtering Data Using WHERE

Querying for a specific address 0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

SELECT *, (_amount / 1e18) as _amount FROM aave."LendingPool_evt_Deposit"
WHERE _reserve = '\xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee'
limit 100

By adding a query condition, we can quickly filter the data we need.

To view deposits with USDC as collateral, use the USDC contract address: xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48

SELECT * FROM aave."LendingPool_evt_Deposit"
WHERE _reserve = '\xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48'
limit 100

The above examples are referenced from Your guide to basic SQL while learning Ethereum at the same time

Practicing On-Chain Transfers

Practice querying transfers in the Ethereum.Transactions table.

select * from ethereum.transactions
LIMIT 10

Field and Transfer Correspondence Explanation

Take this hash transfer as an example.

The transfer is from 0x22fff189c37302c02635322911c3b64f80ce7203 to 0x8aae242452471d2dfea145214ceedf87ca043198

Hash: 0xfa69f5eb0218f56ae602ef7f01588d9193a891e6fe7ba7e1c3994075a689bb51

We can directly query this information using Dune.

select * from ethereum.transactions
WHERE hash='\xfa69f5eb0218f56ae602ef7f01588d9193a891e6fe7ba7e1c3994075a689bb51'

The fields in Dune correspond to those in Etherscan.

Data Visualization

Click on New visualization to choose the desired view. For example, I clicked on bar chart.

This will visualize the data I just filtered. The longest bars represent the accounts with the highest borrowing amounts.

Summary

In this lesson, we introduced the basics of using Dune. With Dune, we can convert on-chain data into visualized data, allowing us to better understand the hotspots on the blockchain.