What's The Difference Between Relation Schema And Relational Database Schema?

Database Schema:   Database schema is a collection of meta-data that describes the relations in a database. A schema can be simply described as the "layout" of a database or the blueprint that outlines the way data is organized into tables. Schema are normally described using Structured Query Language as a series of CREATE statements that may be used to replicate the schema in a new database.

Relation schema: A relation schema can be thought of as the basic information describing
a table or relation. This includes a set of column names, the data types associated
with each column, and the name associated with the entire table.