Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen angezeigt.

--- modul:m290:learningunits:lu03:theorie:a_concept [2024/08/14 10:21] – vdemir
+++ modul:m290:learningunits:lu03:theorie:a_concept [2024/10/02 15:15] (aktuell) – vdemir
@@ Zeile 1: / Zeile 1: @@
-====== LU03a - Concept of a RDB ======
+====== LU04a - Concept of a RDB ======
+==== Learning Objectives====
+  - I can explain in my own words, what a relations database is and why it is widely used in all kinds of web applications.
+  - I can name and explain the key components of a relational database.
 A Relational Database (RDB) is a structured method for storing and organizing data. The core idea is to represent data as related tables.
@@ Zeile 9: / Zeile 15: @@
   * **Fields**: A column in a table, defining the type of data stored in each row.
   * **Relationships**: Connections between tables based on shared data. Common types include one-to-one, one-to-many, and many-to-many relationships.
+==== Structure and Integrity ====
+  * **Primary Key**: A unique identifier for each record in a table.
+  * **Foreign Key**: A field in one table that references the primary key in another table, establishing a relationship.
+  * **Data Integrity**: Ensures data accuracy and consistency through constraints like:
+    * Entity Integrity: Every table must have a primary key with no null values.
+    * Referential Integrity: Foreign key values must match existing primary key values or be null.
+    * Domain Integrity: Data values must conform to defined data types.
+==== Advantages of RDBs ===
+  * **Data Consistency**: Enforced by relationships and constraints.
+  * **Data Security**: Access control mechanisms protect sensitive information.
+  * **Data Independence**: Changes to data structure can be made without affecting applications.
+  * **Efficient Data Access**: Indexing and query optimization enhance performance.
+==== Common RDB Systems ====
+  * MySQL
+  * PostgreSQL
+  * Oracle Database
+  * Microsoft SQL Server
+----
 ===== Vocabulary =====
 ^ English ^ German ^
-| to provide | bereitstellen |
+| row | Zeile |
+| column | Spalte |
+| entity | Objekt(-Einheit) |
+| attribute | Eigenschaft |
+| instance | Exemplar, Beispiel |
+| unique | einzig(-artig) |
+| to reference to | verweisen auf |
+| to establish | errichten, herstellen |
+| consistency | Widerspruchsfreiheit, Übereinstimmung |
+| constraint | Auflage, Bedingung |
+| to enhance | verbessern, aufwerten |
 ===== References =====