Is there any relationship between China National Development and Investment Corporation and CDB?

There is no relationship between the two.

China Investment Company was established in autumn of 2007. Is a wholly state-owned company with a registered capital of 200 billion US dollars, and is in charge of foreign exchange investment.

China Development Bank (CDB) is a development financial institution with national credit, which realizes the government's development goals by building the market.

The former is an investment company and the latter is a financial institution. The source of the former is foreign exchange, not the latter's customers. So there is no relationship between the two.