🔀Token Transfers

crosschain.assets.transfers contains fungible token transfer data for chains indexed by Allium.

This includes native tokens and erc20 equivalent tokens (bep20, trc20) transfers across EVM chains indexed by Allium and SOL & SPL token transfers on Solana.

Understanding Blockchain Transfers

A short primer on understanding Allium's transfer schema.

Introduction

Blockchain transactions are the fundamental building blocks of blockchain networks.

• They involve the transfer of digital assets or information from one party to another.

• When a transaction is performed and confirmed, the details of the transactions are appended to the blockchain, with a unique transaction hash accompanying the transaction.

• By indexing the blockchain, we can identify all transactions and asset transfers.

This guide aims to help users map Allium's transfer schema to the transaction data that they typically observe on blockchain explorers, such as Etherscan.

EVM Chain

Mapping Allium Schemas to EVM-Compatible Blockchains.

EVM-compatible chains are blockchain networks that are compatible with the Ethereum Virtual Machine (EVM).

In this example, we will use a USDT -> USDC transaction performed on the Ethereum network and illustrate how it maps to Allium's data schema.

select * from crosschain.assets.transfers
where chain = 'ethereum'
    and block_timestamp::date = '2024-05-02' -- UTC date to speed up the query
    and token_type = 'erc20'
    and transaction_hash = '0xfe0ae8b623268b552f40bbdb17f07ec9bff70d4fb3139eda8580a48ac299e996'

1. In this transaction, the transaction sender (transaction_from_address) interacted with the Exchange Proxy contract (transaction_to_address).

2. The user (0x23b7) then sends 10,679 Tether USD from its address (from_address) -> Uniswap V3 USDC-USDT contract address (to_address).

3. In turn, the Uniswap V3 contract (from_address) sends 10,687.25 USDC from itself to the user 0x23b7 (to_address).

A user performing a swap from USDT to USDC stablecoin on the Ethereum blockchain. https://etherscan.io/tx/0xfe0ae8b623268b552f40bbdb17f07ec9bff70d4fb3139eda8580a48ac299e996

How does Allium identify these transfers?

For ERC-20 (BEP-20, TRC-20) compatible tokens, transfers will emit a corresponding Transfer event log in their receipts.

We index the entire blockchain and identify and decode these transfers. Receipt event logs are only emitted for successful transfers.

Event log emitted by the Circle USDC token during this transaction.

For Native Tokens, such as Ethereum, Avalanche, BNB token, we identify trace value transfers for successful trace calls.

Gas consumption by the transaction sender (transaction_from_address) is also deducted from the transaction sender.

Native Ethereum (ETH) transferred https://etherscan.io/tx/0x4d8bb55d561350a95b5518e71ea6026f45a385231ad0d01ce112203ff0adca86#internal

Solana

Token Transfers on Solana work differently from EVM chains. To begin, you need to familiarise yourself with the following account types.

Account Types

1. Native Accounts: Handle native programs like System, Vote, Stake.

2. SPL Accounts: Store tokens other than SOL and NFTs.

3. Program Accounts: Execute actions and run instructions.

Transfer Mechanisms

SOL Transfer:

• From User A to User B: Direct and similar to transactions on other blockchains.

SPL Token/NFT Transfer:

• Compartmentalized Storage: Unlike Ethereum's single storage for all ERC-20 tokens, Solana uses multiple compartments within a user account, each dedicated to one type of SPL token.

https://solscan.io/tx/4YWQv62igJbZaUX9ifybtZiK3vqjKim58kspoazp17wJxza4krvrSxFniuqWrojiZ2UJyXMEm1b8YaoenuovX3GM

In this transfer shown, we see that 5hjTw3.. transferred 79.87 USDT to AhhoxZ... The account/address represented here is the wallet account.

Under the hood, when we toggle the "View Token Account" option, the USDT is transferred across the underlying token accounts, which are represented by token_acc_from and token_acc_to

Note on collection of fees with TokenExtension program

Transfer of spl tokens as a result of calling fee collection methods withdrawWithheldTokensFromAccounts and harvestWithheldTokensToMint are not indexed yet. More info here.

This is due to an odd design design in the TokenExtension program, where there is no indication of spl token movement via transfer calls, causing movement of fees to become invisible. More info in this tweet.

Table Columns

Column Name	Description
chain	Currently includes transfers from ethereum, polygon, arbitrum, avalanche, base, bsc, optimism, scroll, polygon_zkevm, tron & solana.
token_type	Type of token transferred. Includes erc20 (for all evm), tr20 (tron). Native tokens include eth, matic, avax & bnb. For solana, spl and system (sol) tokens.
from_address	Address where the token is being transferred to.
to_address	Token address of the asset transferred.
token_acc_from	(Solana-only) The token account that the asset is being transferred from.
token_acc_to	(Solana-only) The token account that the asset is being transferred to.
token_address	Address (or Token Mint on Solana) of the token that is being transferred.
token_name	Name of the asset transferred.
token_symbol	Token symbol of the asset transferred.
raw_amount	Amount of tokens moved (unnormalized).
amount	Amount of token moved, normalized.
usd_amount	The value of tokens moved, in USD. Not all tokens will have accompanying USD value attached.
transaction_from_address	The address of the sending party of this transaction. (For Solana, this maps to the transaction signer)
transaction_to_address	The address of the receiving party of this transaction (could be a contract address). This field is null for Solana.
transaction_hash	Transaction hash of the transfers.
block_timestamp	Block timestamp of the transfers.
block_number	Block number of the transfers.
block_hash	Block hash of the transfers.
unique_id	Unique id generated to each transfer.
extensions	(Solana-only) json object containing information on transfers initiated with solana's TokenExtension program. Current coverage: transfer fees - we include fees in raw_fee_amount. Note that the raw_amount/amount in the main table includes these fees.