If you want an easy way to fetch that hash later on, you can:
- use the contract store: array or mapping
- or use the contract logging system with an event.
event LogMyHash(bytes32 indexed theHash);
. indexed
will ensure you can query by the hash, like a mapping would do.
On the other hand if you did not care about retrieval, but all you wanted to do was quickly add your hash to a dummy transaction, you can send one to your other address and do eth.sendTransaction({ from: you, to: otherYou, data: theHash })
. Since there is no code at your other address, data
will not trigger anything. But the hash is there for anyone who knows where to look.