which is best snowflake or My sql

I would prefer Snowflake over MySQL because Snowflake you can scale up and scale down your compute automatically to accommodate volume. Snowflake also makes the use of Index irrelevant as all the data is stored in a proprietary Snowflake format with the Metadata Layer controlling the route to the data.

Depends on your needs. MySQL is open source/free. It or Postgres (another open source db) is good for pretty much any normal need. You can install on your own equipment. Snowflake is a “designed from the ground up to be a cloud data warehouse” service. There is no version you can install. From an enterprise view, it’s quite inexpensive compared to Teradata or any similar MPP database they are running in their data centers. But it’s not free and open source.