Logs

Logs (or event logs), is a way for smart contracts to communicate with the outside world by "documenting" small pieces of information. Event logs allow other people to know that something has happened without them having to query the contract directly.

The most common form of event logs today are ERC20 (and ERC721) token transfer events.

Table Columns

Column Name	Description
log_index	The position of this log in the block that it belongs to. The first log has index 0.
transaction_hash	Unique identifier of the transaction that this log belongs to.
transaction_index	The position of this transaction in the block that it belongs to. The first transaction has index 0.
address	The address of the contract that emitted this log.
data	Unindexed data containing further information of the event, encoded in hex.
topic0	The keccak256 hash of a flattened event signature string.
topic1	First indexed topic of the event.
topic2	Second indexed topic of the event
topic3	Third indexed topic of the event.
block_timestamp	The time when the block that contains this log was included on the blockchain.
block_number	The length of the chain, in blocks.
block_hash	Unique identifier of the block that includes this log.
_created_at	Timestamp of the entry creation.
_updated_at	Timestamp of the entry update.