Batch schema statements to create multiple SASI and MV at once to reduce disk IO

Currently, operator has to create SASI/MV one by one on the same table and every index/view build will need to read all data on disk.

In order to speed up multiple SASI/MV creation, I propose to add a new batch schema statement to create multiple SASI/MV at once, so that C* only needs to read on-disk data once.