What is tablespace and datafile in Oracle?

What is a data file in Oracle?

Datafiles are physical files of the operating system that store the data of all logical structures in the database. They must be explicitly created for each tablespace. Oracle assigns each datafile two associated file numbers, an absolute file number and a relative file number, that are used to uniquely identify it.

What is a tablespace used for?

A table space is a storage structure containing tables, indexes, large objects, and long data. They are used to organize data in a database into logical storage groupings that relate to where data is stored on a system. Table spaces are stored in database partition groups.

What tablespace means?

A tablespace is a storage location where the actual data underlying database objects can be kept. It provides a layer of abstraction between physical and logical data, and serves to allocate storage for all DBMS managed segments.

How many datafiles can a tablespace have?

A smallfile tablespace is a traditional Oracle tablespace, which can contain 1022 datafiles or tempfiles, each of which can contain up to approximately 4 million (222) blocks. Dependent on the operating system. An external table can be composed of multiple files.