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How does smart contract use oracle
2022-02-03 23:11:46 【Q & A of Denglian community】
Because the contract itself cannot take the initiative to call , How to get the data of the Oracle , A method of artificially executing a contract , Then the method in the contract calls the interface of the oracle , Is that right ？
Take the answer 1：
It's usually like this , Make a request to the oracle in the contract ： What kind of data do I need to declare , This request needs to be accompanied by a callback function , After the Oracle gets the data , The callback function will be called to send the data to the contract .
Reference resources Use Chainlink Predicting machine
Other answers 1：
author[Q & A of Denglian community],Please bring the original link to reprint, thank you.
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