Can I read state variables or not?

xiaoyao1991 / presto-ethereum

Presto Ethereum Connector -- SQL on Ethereum

Apache License 2.0

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Can I read state variables or not? #37

Open georgek146 opened 6 years ago

georgek146 commented 6 years ago

I'm confused can I only read events or state variables too?

xiaoyao1991 commented 6 years ago

In short, no you can't read state variables.

On Thu, Mar 29, 2018 at 06:18 George K notifications@github.com wrote:

I'm confused can I only read events or state variables too?

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georgek146 commented 6 years ago

Ok. In the other issue you say this is possible. What do you mean by having a having an instrumented ethereum client? What is that?

xiaoyao1991 commented 6 years ago

An instrumented client could be, for example, a modified geth client where you store the EVM traces, decode the traces so that those info can be queried through presto.

georgek146 commented 6 years ago

Why not just abstract some of the calls to web3?

georgek146 commented 6 years ago

Also what would it take to be able to create a transaction on ethereum with sql? If we could build that that would be extremely valuable.

xiaoyao1991 commented 6 years ago

@georgek146 "Why not just abstract some of the calls to web3?"

It can be done, but I wonder how useful it is. Essentially it only allows you to select right? No aggregation can be done.

"Also what would it take to be able to create a transaction on ethereum with sql? If we could build that that would be extremely valuable."

Very interesting thought. I have actually thought about this too. Create a SQL-based ethereum client. Inserting record could be sending tx or mining blocks :) Just didn't have the time to dig into the "write" part of presto yet. Would you like to take lead on that?

georgek146 commented 6 years ago

The problem that I see many contract developers face is storage organization. I was thinking that we write a contract that basically represents a table. A user could deploy the contract by using an SQL statement, and then be able to execute further state changes through SQL.

georgek146 commented 6 years ago

I could write the contract, however I would not know how to take a SQL statement and convert that into calling solidity functions.

georgek146 commented 6 years ago

Creating a new client would be beyond my skill level