Accessing data at a specific chain node

[ghost]

How can I efficiently query specific blockchain nodes to retrieve data related to a particular wallet address? Could you provide an overview of the best practices and workflow for accessing this data, including any recommended tools or APIs?
Assuming there are millions of nodes, a brute force way of checking with every node seems very inefficient in the worst case. Wondering if there is a more efficient algorithm to achieve this.

[toliaqat]

Agoric's mainnet has 100 validators, not millions of nodes.

RPC (Remote Procedure Call) nodes in the Cosmos-SDK ecosystem make it easy to interact with the blockchain. They let users query data and submit transactions without needing to contact every node. However, relying on a single RPC node can be risky because if it goes down or is compromised, access to the blockchain can be disrupted.

To avoid these issues, connect to multiple, randomly selected nodes. This spreads the risk and reduces the chance of encountering a compromised node, promoting decentralization.

The best approach is to run your own RPC node. This gives you full control and avoids relying on third-party nodes, though it requires technical skills, a stable internet connection, significant storage, and regular maintenance.

Here are the curl and equivalent agd commands to fetch the balances of an account by connecting with a mainnet RPC node:

curl https://main.api.agoric.net:443/cosmos/bank/v1beta1/balances/<agoric1 address>
agd --node https://main.rpc.agoric.net:443 query bank balances <agoric1 address>