Oracle SQL enables you to create and manipulate many other types of schema objects.
The principal types of schema objects are shown in the following table.
Table 2-1 Schema Objects
| Object | Description | To Learn More |
|---|---|---|
| Table | A table stores data in rows. Tables are the most important schema objects in a relational database. data analytics | “Overview of Tables” |
| Indexes | Indexes are schema objects that contain an entry for each indexed row of the table or table cluster and provide direct, fast access to rows. Oracle Database supports several types of index. An index-organized table is a table in which the data is stored in an index structure. | “Indexes and Index-Organized Tables” |
| Partitions | Partitions are pieces of large tables and indexes. Each partition has its own name and may optionally have its own storage characteristics. | “Overview of Partitions” |
| Views | Views are customized presentations of data in one or more tables or other views. You can think of them as stored queries. Views do not actually contain data. | “Overview of Views” |
| Sequences | A sequence is a user-created object that can be shared by multiple users to generate integers. Typically, you use sequences to generate primary key values. | “Overview of Sequences” |
| Dimensions | A dimension defines a parent-child relationship between pairs of column sets, where all the columns of a column set must come from the same table. Dimensions are commonly used to categorize data such as customers, products, and time. | “Overview of Dimensions” |
| Synonyms | A synonym is an alias for another schema object. Because a synonym is simply an alias, it requires no storage other than its definition in the data dictionary. | “Overview of Synonyms” |
| PL/SQL subprograms and packages | PL/SQL is the Oracle procedural extension of SQL. A PL/SQL subprogram is a named PL/SQL block that can be invoked with a set of parameters. A PL/SQL package groups logically related PL/SQL types, variables, and subprograms. | “PL/SQL Subprograms” |
Other types of objects are also stored in the database and can be created and manipulated with SQL statements but are not contained in a schema. These objects include database user account, roles, contexts, and dictionary objects.
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