Difference Between Schema and Table

Schema vs Table

(数据库)模式是t的正式描述he organization and the structure of data in the database. This description includes the definitions of tables, columns, data types, indexes and much more. In a database, a table is a data set in which the data is organized in to set of vertical columns and horizontal rows. Number of columns in a table is specified in the database schema, but it can hold any number of rows. Tables also contain information such as constraints on the values in the columns and this information are called meta-information.

What is a Schema?

A database schema of a database system describes the structure and the organization of data. A formal language supported by the Database Management System is used to define the database schema. Schema describes how the database will be constructed using its tables. Formally, schema is defined as the set of formula that imposes integrity constraints on the tables. Furthermore, the database schema will describe all tables, column names and types, indexes, etc. There are three types of schema called the conceptual schema, logical schema and physical schema. Conceptual schema describes how concepts and relationships are mapped. Logical schema defines how entities, attributes and relations are mapped. Physical schema is a specific implementation of the aforementioned logical schema.

What is a Table?

A table is a set of data that is organized in to rows and columns. A database contains one or more tables that actually hold the data in the database. Each table in a database has a unique name that is used to identify it. Columns in a database also have a unique name and a data type associated with it. In addition, there can be special attributes associated with a column such as whether it is a primary key or whether it is used as an index, etc. The rows in a table hold the actual data. In relational databases, a relation is represented using a table. But a relation and a table are not the same, since a table can have rows that are duplicates (and a relation cannot contain duplicate rows). There are two types of tables as object tables and relational tables. Object tables hold objects of a defined type whereas relational tables hold user data in a relational database.

What is the difference between Schema and Table?

A database schema describes the structure and organization of data in a database system, while a table is a data set in which the data is organized in to a set of vertical columns and horizontal rows. The database schema defines the tables in a database, the columns and their types. In addition the schema also defines what columns are defined as the primary key of a table. Understandably, the schema of a database keeps constant once created, while the actual data in the database tables may change all the time.