How to store encrypted data in a database?

Question

Database design

There is a need to encrypt some data that is stored in the database.
At the moment I'm leaning towards the cassandra database stack and RSA 2048 encryption

. For example, there is a table of users id, name, phone. The goal is to encrypt data from the phone column.

And here I have 2 options:
1) enter encrypted data directly in the user table in the phone column
2) select a separate table id, keyId, value (keyId is the encryption key identifier, value is the hash) and store the encrypted data id in the phone column.

Actually why are there 2 options.
Option 1 is simple.
Option 2 will allow you to change the encryption keys by decrypting the value, creating a new string with a hash from the new encryption key, and simply overwriting the string id in the phone field. It will also allow you to move encryption / decryption to a separate service with separate access to the database.

There is still a question with the search for encrypted data, if you have any thoughts - share :)
I will also not refuse criticism about the stack

Answer 1

How to store encrypted data in a database?

It is not necessary to do this, because. if the data in the database is encrypted, then your database ceases to be such, and begins to be just a garbage dump with a bunch of encrypted data, search, sorting, selection, queries, etc. stop working.
You need to encrypt the database itself, not the data in it.