The role of views in oracle
A view in Oracle is a virtual table that provides different perspectives on data. Its main functions include: data abstraction, data security, data conversion, data integration and performance optimization. Benefits include: no storage space, data consistency, improved performance, enhanced security, and simplified data access. The disadvantages are: it may affect query performance, does not support data updates, and requires regular maintenance.
The role of views in Oracle
A view is a virtual table in Oracle, which is based on one or more Basic table creation, providing different perspectives on the data. Views do not store actual data, but instead return results in real time when queried.
The main function of views:
- Data abstraction: Views can hide the complex structure of the underlying table and provide users with a simplified data representation.
- Data Security: Views can restrict access to sensitive data, allowing users to see only the information they are authorized to see.
- Data transformation: Views can apply transformations and aggregations to present data to users in different ways.
- Data integration: Views can combine data from different tables to create integrated views.
- Performance optimization: Views can pre-compute the results of complex queries to improve the performance of subsequent queries.
- Simplify application development: Views can simplify application development because developers can use a different representation of data than the actual table.
Advantages of views:
- Does not occupy physical storage space
- Maintains data consistency
- Improves Application Performance
- Enhanced Data Security
- Simplified Data Access and Management
Disadvantages of Views:
- May affect query performance
- Does not support data updates
- Requires regular maintenance to reflect changes in the underlying table
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