Oracle Database Administration from Zero to Hero - Using External Tables

This lecture covers the use of external tables in Oracle databases, focusing on Oracle Loader and Data Pump drivers. It explains how to create external tables, the syntax involved, and the benefits of using parallel processing. The lecture also discusses the process of unloading and loading data using Oracle Data Pump, highlighting the importance of knowing table structures and using parallelism for efficiency.

What is the primary purpose of using external tables in Oracle databases?

• To store data permanently in the database

• To access data in external files without copying it into local tables

• To perform complex calculations on data

• To enhance the security of the database

Which driver is used by the SQL Loader utility?

• AXIS Driver

• External File Driver

• Oracle Data Pump

• Oracle Loader

What is a limitation of the Oracle Loader driver?

• It cannot read from flat files

• It cannot create, update, or append to an external file

• It cannot be used for data migration

• It cannot be used with CSV files

What is the first step in creating an external table using the Oracle Loader driver?

• Define the access driver

• List the columns in the table

• Specify the default directory

• Provide the data file name

What is the purpose of the REJECT LIMIT UNLIMITED clause?

• To limit the number of records processed

• To set the maximum allowable number of rejected records to an unlimited value

• To specify the directory for log files

• To define the data file format

Why is parallel processing beneficial when using the Oracle Loader driver?

• It increases the security of the data

• It reduces the size of the data files

• It simplifies the syntax of the CREATE TABLE statement

• It allows multiple sessions to access the external table concurrently

What is the main advantage of using the Oracle Data Pump driver?

• It allows for real-time data updates

• It enables unloading and loading of data into external binary files

• It supports more file formats than Oracle Loader

• It is faster than Oracle Loader

What must be known in advance to load an external table using Oracle Data Pump?

• The security settings of the database

• The size of the data file

• The table structure

• The number of parallel processes

How can the performance of unloading and loading Oracle Data Pump external tables be improved?

• By using smaller data files

• By using a different access driver

• By increasing the number of dump files

• By reducing the number of columns

What is a key consideration when transferring data using Oracle Data Pump?

• The data must be in CSV format

• The output dump file is not secure by default

• The data cannot be transferred to a cloud storage

• The output dump file is secure by default