Oracle Database Concepts: introduces the Schema Objects (Introduction to Schema Objects) and conceptsschema

Oracle Database Concepts: introduces the Schema Objects (Introduction to Schema Objects) and conceptsschema

Database schema is a logical container of data structures. It is called schema objects)

Each database user has the same mode as the user name. For example, the hr user has the hr mode.

In a product database, the model owner is usually a database application rather than a person.

In a mode, each mode object has a unique name. For example, hr. employees indicates the employees table in hr mode.

As shown in:

 

Pattern object type

The most important schema object is a table in a relational database. Oracle SQL allows you to create and operate on schema objects of other types. As follows:

1. Index (Indexes)

2. Partition)

3. Views)

4. Sequences)

5. Dimensions)

6. Synonyms (Synonyms)

7. PL/SQL subprograms and packages (PL/SQL subprograms and packages)

 

Mode Object Storage

In the logical storage structure, some schema object storage data is called segments ).

The storage mode of the Oracle database is logically in a table space. The table space has nothing to do with the mode: A table space can contain different modes, objects in one mode can be included in different tablespaces. The data of each object is physically contained in one or more data files.

This is a possible configuration. The data segment (segment) of a table spans two data files. Both data files are in the same tablespace. A segment cannot span multiple tablespaces.

 

Dependencies)

Some schema objects reference other objects. For example, if object A references object B, A is A dependent object and B is A referenced object.

Oracle Database provides an automatic mechanism to ensure that dependent objects always represent the latest referenced objects.