Book Image

Developing Robust Date and Time Oriented Applications in Oracle Cloud

By : Michal Kvet
Book Image

Developing Robust Date and Time Oriented Applications in Oracle Cloud

By: Michal Kvet

Overview of this book

Proper date and time management is critical for the development and reliability of Oracle Databases and cloud environments, which are among the most rapidly expanding technologies today. This knowledge can be applied to cloud technology, on premises, application development, and integration to emphasize regional settings, UTC coordination, or different time zones. This practical book focuses on code snippets and discusses the existing functionalities and limitations, along with covering data migration to the cloud by emphasizing the importance of proper date and time management. This book helps you understand the historical background and evolution of ANSI standards. You’ll get to grips with data types, constructor principles, and existing functionalities, and focus on the limitations of regional parameters and time zones, which help in expanding business to other parts of the world. You’ll also explore SQL injection threats, temporal database architecture, using Flashback Technology to reconstruct valid database images from the past, time zone management, and UTC synchronization across regions. By the end of this book, you’ll be able to create and manage temporal systems, prevent SQL injection attacks, use existing functionalities and define your own robust solutions for date management, and apply time zone and region rules.
Table of Contents (26 chapters)
1
Part 1: Discovering Oracle Cloud
4
Part 2: Understanding the Roots of Date and Time
7
Part 3: Modeling, Storing, and Managing Date and Time
12
Part 4: Modeling Validity Intervals
17
Part 5: Building Robust and Secure Temporal Solutions
20
Part 6: Expanding a Business Worldwide Using Oracle Cloud

Modeling a calendar using SQL

Although it is possible to hardcode a calendar using a PL/SQL block, it can look a bit complicated at first sight.

Now, let’s look at the monthly calendar definition using SQL. For simplicity, we will use the month extracted from the sysdate value, but generally, it can be applied to any specified DATE value. Note that the processing can be optimized by grouping multiple select statements together. However, for explanatory purposes, step-by-step processing is more convenient. Therefore, individual steps are nested. Each step takes the data from the preceding processing.

Step 1 – Getting the day numbers for each day in the month

The goal of this step is to get the same number of rows as the number of days in the month. To do that, the dual table is referenced, which holds just one row. Therefore, the CONNECT BY LEVEL clause is used with the value expressing the numerical representation of the difference between the last day of the...