Oracle 10g Database Fundamentals Tutorial: Answers376

1. What is Oracle?

Oracle is a relational database management system (RDBMS) that stores and retrieves data in an organized and efficient manner. It is widely used in various industries for managing large amounts of data.

2. What are the key components of an Oracle database?

The key components of an Oracle database include:
Instance - A running copy of an Oracle database that manages database processes and memory structures.
Database - A container for data that is organized into tablespaces, tables, and rows.
Tablespaces - A collection of related data files that store specific types of data.
Tables - A collection of rows and columns that hold related data.
Rows - A set of values that represent a specific entity or record.
Columns - A set of fields that describe the characteristics of a specific entity.

3. What are the different types of data types in Oracle?

Oracle supports a variety of data types, including:
Numeric - Numbers, such as INTEGER, FLOAT, and DECIMAL.
Character - Text strings, such as VARCHAR2 and CHAR.
Date - Dates and times, such as DATE and TIMESTAMP.
BLOB - Binary large objects, such as images and videos.
CLOB - Character large objects, such as large text documents.

4. What are the fundamental SQL commands?

The fundamental SQL commands include:
SELECT - Retrieves data from tables.
INSERT - Adds new rows to a table.
UPDATE - Modifies existing rows in a table.
DELETE - Removes rows from a table.
CREATE TABLE - Creates a new table.
ALTER TABLE - Modifies an existing table.
DROP TABLE - Deletes an existing table.

5. What are the different constraints in Oracle?

Oracle supports various constraints to enforce data integrity, including:
NOT NULL - Ensures that a column cannot have null values.
UNIQUE - Ensures that each value in a column is unique.
PRIMARY KEY - Identifies rows uniquely within a table.
FOREIGN KEY - Establishes a relationship between rows in different tables.

6. What is an index in Oracle?

An index is a data structure that speeds up data retrieval by organizing table data based on specific columns. It allows for faster access to data without having to scan the entire table.

7. What is a view in Oracle?

A view is a virtual table that represents a subset of data from one or more tables. It provides a customized perspective of the data without modifying the underlying tables.

8. What is a stored procedure in Oracle?

A stored procedure is a set of SQL statements that are stored in the database and can be executed multiple times with different parameters. They allow for complex data manipulation tasks to be encapsulated and reused.

9. What is a trigger in Oracle?

A trigger is a database object that automatically executes a set of actions when a specific event occurs, such as inserting, updating, or deleting data in a table. They are used to enforce business rules and maintain data integrity.

10. What are the key differences between Oracle 10g and Oracle 11g?

Key differences between Oracle 10g and Oracle 11g include:
Improved performance and scalability
Enhanced security features
Simplified administration
New data types and features

2024-12-06

Previous：Zhang Wentong SPSS Statistical Analysis Basic Tutorial Data

Next：Oracle 11g Database Essential Guide for Beginners