What are schemas in PrestoDb?

Question

I am reading this post that explains concepts in presto.

I am really confused by the definition of Schemas. The post says

Schema is what you use to organize your tables.

This is confusing to me because I have always thought of schema's as a way to describe the shape of a table. Ie the columns present and the types of the columns.

So this line is telling me Schema is a way to organize my tables? What does that even mean?

I am familiar with databases like MySQL, and I have mostly interacted with databases, and the tables contained within those databases

Presto seems to be introducing another concept of Schemas? And I find this confusing how it fits into the big picture.

So please what exactly are schemas in prestoDB?

Answer 1

Presto seems to be introducing another concept of Schemas?

No, it does not.

Have not worked with MySQL but other databases like SQL Server (docs, SO Answer) and Postgres (docs) has the same concept of schemas (just schemas, not table schemas) too - they are used to organize tables in the database. From the PostgreSQL docs:

There are several reasons why one might want to use schemas:

• To allow many users to use one database without interfering with each other.
• To organize database objects into logical groups to make them more manageable.
• Third-party applications can be put into separate schemas so they do not collide with the names of other objects.