Assuming that you are happy to use a 3rd party service (such as blockchain.info) then you could skip the rescan (i.e. just dump the wallet addresses to search using the 3rd party service).
That should at least making doing the balance checks quicker.
and you could even write a script to do that using curl and the third party api
Would be easier to just dump the private keys instead of public addresses and then sweep with electrum, no?
How can I dump the private keys without pywallet?, The dump feature in Core requires core to be loaded afaik.
my intention is to sweep the keys to a single address.
Core doesn't need to be synced (or resynced) to dump the private keys, so you're script would be:
Delete wallet.dat in Core Folder
Copy wallet_x -> wallet.dat in Core Folder
Start Core (wait for Core API to be online)
Query Core API to dump private key(s)
Terminate Core (wait for shutdown)
Repeat
Then you have all dumped private keys and sweep with electrum to 1 address
Is this with bitcoind? im currently on windows using bitcoin-qt
I am getting the following error when I try to connect to the json RPC interface anytime after launch (until it loads fully)
{"result":null,"error":{"code":-28,"message":"Rescanning..."},"id":"dumpwallet"}
This shows a successful connection as it knows its rescanning, but will not do anything else.