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Chapter one : Fundamental Concepts of Database Management

Concurrency control is a database management systems (DBMS) concept that is used to address occur with a multi-user system. Concurrency control, when applied to a DBMS, is meant to coordinate simultaneous transactions while preserving data integrity.

In database systems, isolation determines how transaction integrity is visible to other users and systems. For example, when a user is creating a purchase order and has created the header, but not the purchase order lines, is the header available for other systems or users (carrying out concurrent operations, such as a report on purchase orders) to see?

Chapter two: Architecture and Categorization of DBMSs

Chapter 3 : Conceptual data modelling A weak entity type is always existence dependent (= minimum cardinality is 1) from owner entity type (not vice versa)

Composite is book

A private access modifier is denoted with a ‘-‘, public with ‘+’ and protected with ‘#’.

Chapter 6 : Relational databases Normalization : https://www.youtube.com/watch?v=l5DCnCzDb8g

Boek p 127

Since a department can have multiple employees, we cannot add a foreign key to it as this would create a multi-valued attribute type , which is not tolerated in the relational model. Since the minimum cardinality is one, this foreign key is defined not null , ensuring that an employee works in exactly one department.

PUBLISHERNAME == FOREIGN KEY. “ a book can have multiple publisherz”

NIEUW

CHAPTER 7 : SQL Note: The WHERE clause is not only used in SELECT statement, it is also used in UPDATE, DELETE statement, etc.! Note: Be careful when updating records in a table! Notice the WHERE clause in the UPDATE statement. The WHERE clause specifies which record(s) that should be updated. If you omit the WHERE clause, all records in the table will be updated! Note: Be careful when deleting records in a table! Notice the WHERE clause in the DELETE statement. The WHERE clause specifies which record(s) should be deleted. If you omit the WHERE clause, all records in the table will be deleted! The LIKE operator is used in a WHERE clause to search for a specified pattern in a column.

The IN operator allows you to specify multiple values in a WHERE clause. The IN operator is a shorthand for multiple OR conditions.

The GROUP BY statement groups rows that have the same values into summary rows, like "find the number of customers in each country". The GROUP BY statement is often used with aggregate functions (COUNT, MAX, MIN, SUM, AVG) to group the result-set by one or more columns.

Chapter 15 : Accessing Databases and APIs

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Chapter 11 : NoSQL Databases

Chapter 4, 17, 18 Organizational aspects

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Data warehouse focuses on insert/select statements

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Chapter 12, 13 and 14 : From logical concepts to physical constructs...