Some schema objects store data in a type of logical storage structure called a segment. For example, a nonpartitioned heap-organized table or an index creates a segment.
Other schema objects, such as views and sequences, consist of metadata only. This topic describes only schema objects that have segments.
Oracle Database stores a schema object logically within a tablespace. There is no relationship between schemas and tablespaces: a tablespace can contain objects from different schemas, and the objects for a schema can be contained in different tablespaces. The data of each object is physically contained in one or more data files.
The following figure shows a possible configuration of table and index segments, tablespaces, and data files. The data segment for one table spans two data files, which are both part of the same tablespace. A segment cannot span multiple tablespaces.
Figure 2-2 Segments, Tablespaces, and Data Files
Description of “Figure 2-2 Segments, Tablespaces, and Data Files”
See also
- “Logical Storage Structures” to learn about tablespaces and segments
- Oracle Database Administrator’s Guide to learn how to manage storage for schema objects
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