What data objects are there in oracle
Oracle database data objects include: tables (stored data collections), views (virtual tables), sequences (automatically generate unique values), indexes (to speed up retrieval), primary keys (uniquely identify rows), foreign keys ( Connect table data), triggers (automatically execute code), stored procedures (encapsulate tasks), functions (return calculated values), packages (reuse code collections).
Oracle Data Objects
Oracle database contains the following types of data objects:
Table
- Stores a collection of related data.
- consists of rows and columns. The row represents a single record and the column represents the field.
- Each table has a unique primary key column that identifies each row.
View
- A virtual table that derives data from a table.
- Allows users to access and query data in specific ways without having to access the underlying tables directly.
Sequence
- Automatically generate unique values that increase in a specific sequence.
- Typically used for primary keys and other columns that require unique identifiers.
Index
- Data structure that speeds up data retrieval.
- Shortcuts created based on column values can quickly locate specific records.
Primary key
- The column or column combination that uniquely identifies each row in the table.
- Make sure there are no duplicate data rows in the database.
Foreign key
- Connects a column in one table to a primary key column in another table.
- Maintain data integrity and consistency.
Trigger
- Code that is automatically executed when certain events occur.
- Can be triggered when data is inserted, updated, or deleted to perform additional processing or validation.
Stored Procedure
- A set of precompiled SQL statements that encapsulate a specific task.
- Improve performance and simplify complex queries and operations.
Function
- Returns a user-defined code for a specific calculation or value.
- Can be used as calculation in SQL query or stored procedure.
Package
- A reusable collection of related functions, procedures, variables, and other objects.
- Promote code organization and modularity.
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