datbase 5

ما انواع

sql joins ?

• JOIN ALL

• INNER SELECTINNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN, CROSS JOIN, SELF JOIN

• OUTER JOIN

ما اهمية الفهرسة

indexing

في قاعدة البيانات ؟

• 
  Indexing in SQL is used to create backups of databases.

• 
  Indexing in SQL is a technique to enhance data retrieval speed, providing benefits like faster queries and reduced I/O operations.

• Indexing in SQL is a method to delete data quickly

• Indexing in SQL is a technique to encrypt sensitive data.

How do stored procedures enhance database performance?

• Stored procedures eliminate the need for indexing

• 
  

  Stored procedures require more manual coding.

• 
  Stored procedures increase network latency.

• 
  Stored procedures reduce network traffic, allow pre-compilation, and optimize query execution.

List common data types used in SQL

• NCHAR, JSON, SET

• 
  CHAR, TIME, BLOB

• INTEGER, VARCHAR, DATE, BOOLEAN, FLOAT, TEXT, TIMESTAMP

• DECIMAL, CLOB, XML

Explain the ACID properties of transactions.

• Atomicity, Consistency, Isolation, Reliability

• Accuracy, Consistency, Isolation, Durability

• 
  Atomicity, Consistency, Integrity, Durability

• 
  ACID properties: Atomicity, Consistency, Isolation, Durability.

What is a rollback in transaction management?

• 
  A rollback is a process that undoes changes made in a transaction to maintain data integrity.

• A rollback is a technique used to speed up transaction processing.

• 
  A rollback is a process that creates a new transaction without affecting existing data.

• 
  A rollback is a method to permanently save changes in a transaction.

What is the difference between a unique key and a primary key?

• 
  Both primary key and unique key can have multiple null values but serve different purposes.

• A primary key can have multiple null values, while a unique key cannot.

• 
  A primary key cannot be null and uniquely identifies records, while a unique key can allow one null value and

• A unique key is used for foreign key relationships, while a primary key is not.

ماذا تقصد بالعلاقات من واحد إلى العديد؟

one to many

• 1. قد يكون لدى العديد من المعلمين العديد من الفصول الدراسية

• 1. قد يكون لدى العديد من الفصول العديد من المعلمين

• 1. يمكن لمعلم واحد أن يكون لديه العديد من الفصول الدراسية

• 1. قد يكون للفصل الواحد العديد من المعلمين

مجموعة ضخمة من المعلومات أو البيانات المتراكمة من عدة مصادر مختلفة تُعرف باسم

________:

• 1. مستودع البيانات

  2. datawarehouse

• 1. استخراج البيانات

• 1. إدارة البيانات

In which of the following formats data is stored in the database management system?

• Table

• Graph

• Text

• Image