Store privite data on zcash

what if i send data using shilded transcation to the blockchain . is this data readable by nodes and other pepole ? for example in ethereum blockchain when you send input data in transaction its simply readable for every one

how much privicy does zec offer ? is it possible to read data again (only acess by memo key or tx creator ) ?

purpose is using zcash blockchain as privite database to store data and use them again later

You can send a Private transaction with a encrypted memo in it. It will not be visible to anyone but the sender (you) and whoever received the payment. The payment can be very small to make storing information like that very cheap. Even if you look up the TXID on the Blockchain, the private data is not visible.

For example this private transaction: Transactions - Zchain

For the memo to be private you need to send from a Z address to a Z address. Don’t use a T (transparent) address.