The udf_decode_function_call method is a utility function that can be used in SQL queries to decode the input data of an Ethereum transaction. It is designed to work with the ABI (Application Binary Interface) of a contract function, which defines the inputs, outputs, and other details of the function.

Here's how you can use the udf_decode_function_call method in a Markdown tutorial:


The syntax for the udf_decode_function_call method is as follows:

udf_decode_function_call('Contract function ABI', input_data) AS decoded_data
  • Contract function ABI: This is a JSON-formatted string that describes the function signature and its parameters. It follows the Ethereum ABI specification.
  • input_data: This is the actual data from the transaction that needs to be decoded. It is typically stored as a hexadecimal string in the input field of an Ethereum transaction.
  • decoded_data: This is the output column that will contain the decoded information. The data is structured as per the ABI specification, making it easy to understand and work with.


Here's an example of how you might use the udf_decode_function_call method in a query:

  to_address AS contract_address
, block_number
, block_timestamp
, hash AS transaction_hash
, transaction_index AS log_index
, from_address
, to_address
, udf_decode_function_call('{"inputs":[{"internalType":"address","name":"_to","type":"address"},{"internalType":"uint256","name":"_value","type":"uint256"},{"internalType":"uint64","name":"_gasLimit","type":"uint64"},{"internalType":"bool","name":"_isCreation","type":"bool"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"depositTransaction","outputs":[],"stateMutability":"payable","type":"function"}', input) AS decoded_data
FROM ethereum_transactions
WHERE date(block_timestamp) >= date'2023-06-28'
AND to_address = '0x1a0ad011913a150f69f6a19df447a0cfd9551054'
AND substring(input,1,10) = '0xe9e05c42';

In this example, we're querying the ethereum_transactions table to find transactions where the to_address matches a specific smart contract address, and the input data starts with a specific prefix. We then use the udf_decode_function_call method to decode the function call data for these transactions.


The udf_decode_function_call method is a powerful tool for analyzing Ethereum transactions and smart contract interactions. By decoding the input data, you can gain valuable insights into the transactions and the functions that were called. This can be particularly useful for auditing, debugging, and monitoring smart contract activity.

This tutorial provides a basic introduction to the udf_decode_function_call method and how it can be used to decode function calls in Ethereum transactions. For more advanced use cases or specific requirements, you may need to refer to the official documentation or consult with a Footprint Analytics expert.