On-chain data science guide, queries, and tools

Data sources and use cases

1. Dune Analytics (& Flipside):
   • Mostly for gathering business intelligence, such as volume / user market share
   • Advantages: convenient abstraction tables + easy visualization tools
   • Disadvantages: runtime limits + hard to modularize & plug in to other workflows; SQL support only
   • Tips:
     1. use pro-version to download the data in csv format; Flipside has batched api processes that’s easy to setup; Dune is also beta releasing api access for select users
     2. Speed up query by exploring through “Explain”
     3. Address labels are helpful: https://dune.com/labels
2. GCP Bigquery
   • Ethereum-ETL public data
   • Indexed by google and accessible as public data
   • Derived Protocol-level data using ABI parser 4. Events 5. Traces
   • Support user upload of additional data to be merged
   • Advantages: fast, sql-based, multiple methods to access
   • Disadvantages: Lacking stateful data without construction from events/traces; currently only support Ethereum, Polygon; missing Solana data
   • Tips: Use Etherscan or equivalent decoders (e.g. https://ethtx.info/) to extract data
3. Subgraph
   • Stateful data that supplements events/traces
   • Advantages: indexing of data that is not available elsewhere (beyond event emits)
   • Disadvantages: very slow + potential unknown data quality depending on the protocol; someone needs to write and maintain the indexer, usually done by dev team from protocols
4. Archive node calls
   • Services such as Moralis make node call easy
   • Used to query on-chain data that is not normally indexed by data providers, e.g. call smart contract functions to extract output that historically might never have been called
   • Usually helpful to use web3.py and web3.js to facilitate calling and parsing the node
   • Advantages: ability to extract counterfactual data that was not generated/emitted, or smart contract information that’s not readily available e.g. what would the price impact of trading x amount of token pair be through a dex? Test if a token have fee-on-transfer by calling the contract
   • Disadvantages: running a node is expensive and function calls are slower than obtaining parsed data if data exists
5. Other data sources
   • Nansen.ai : Has labeling of addresses that can be useful
   • TRM Labs/Chainalysis: mapping of addresses to entities, particularly KYC’d entities

Helpful blog posts

• https://alexkroeger.mirror.xyz/0C3EQBtFqAK4k2TAGPZhg0JMY-upfTAxuTD-o91vBPc
• https://medium.com/linum-labs/everything-you-ever-wanted-to-know-about-events-and-logs-on-ethereum-fec84ea7d0a5
• https://medium.com/coinmonks/querying-data-in-an-ethereum-blockchain-86289d3fc385
• https://twitter.com/Logvinov_Leon/status/1481618513806696451
• https://towardsdatascience.com/graphql-walkthrough-how-to-query-crypto-with-uniswap-defi-e0cbe2035290