Need help and advice!

[chariotfire]

My bitcoin number shown on my bitcoin core wallet is different with the record on bitcoin block explorer. I had updated all data. On the website, I found out that one trade happened in Dec 2013 might has problem. On my wallet, it shows I only transfer 0.05 btc to the exchange "BTCC". But on bitcoin block explorer, it is showed that I transferred 0.05+4 btc. Actually I remembered I only transfered 0.05 btc. So I      wonder what is going on here, and which number is correct, the wallet, or the explorer? Thank you!

[AB de Royse777]

Do you have a tx to share?

On a side note, may be the core needs to have a full synchronization. 

[LoyceV]

On my wallet, it shows I only transfer 0.05 btc to the exchange "BTCC". But on bitcoin block explorer, it is showed that I transferred 0.05+4 btc. Actually I remembered I only transfered 0.05 btc.

This sounds like a change address: whenever you send Bitcoin, the entire amount (in that input) has to be used at once. If you had 4.05 BTC and sent 0.05 BTC to an exchange, the remaining 4 BTC is send to a change address, which should be part of your own wallet.

[bob123]

Both are correct.

As LoyceV has mentioned, the whole input has to be 'consumed'.

You can compare it to a dollar bill.
You can't just give someone 1/10 of bill. You give the whole bill (bitcoin's UTXO) and get new bills / change back (new UTXO's being created).

Your wallet should show that you still own these 4 BTC, is this the case ?
If so, everything went as expected.

[bitmover]

This sounds like a change address: whenever you send Bitcoin, the entire amount (in that input) has to be used at once. If you had 4.05 BTC and sent 0.05 BTC to an exchange, the remaining 4 BTC is send to a change address, which should be part of your own wallet.

This change address is a newly created address, which is yours.

On my wallet, it shows I only transfer 0.05 btc to the exchange "BTCC". But on bitcoin block explorer, it is showed that I transferred 0.05+4 btc. Actually I remembered I only transfered 0.05 btc. So I      wonder what is going on here, and which number is correct, the wallet, or the explorer? Thank you!

The wallet and the block explorer are correct. Don't worry, as your wallet is showing the correct balance, because that address is part of your wallet

[Thirdspace]

On my wallet, it shows I only transfer 0.05 btc to the exchange "BTCC". But on bitcoin block explorer, it is showed that I transferred 0.05+4 btc.

your wallet only shows the amount leaving your wallet, which as you said 0.05 btc
while block explorer shows the full details on that transaction
you can see the same on your bitcoin core by opening the transaction details on your transaction
for technicalities, LoyceV and bob123 has explained pretty clear on their posts

My bitcoin number shown on my bitcoin core wallet is different with the record on bitcoin block explorer.

bitcoin core wallet shows total bitcoin you have in your wallet, in multi addresses that you have
block explorer shows balance only on specific bitcoin address, they don't know all addresses in your wallet

[chariotfire]

Thanks guys, these comments are very helpful!!