Pagination best practices

Introduction In this article, we are going to discuss several data pagination best and worst practices. Data pagination is omnipresent in enterprise applications. Yet, most solutions, not only they offer a bad user experience, but they are also inefficient.

A beginner’s guide to database table relationships

Introduction In a relational database, a relationship is formed by correlating rows belonging to different tables. A table relationship is established when a child table defines a Foreign Key column that references the Primary Key column of its parent table. Every database table relationship is, therefore, built on top of Foreign Key columns, and there can be three table relationship types: one-to-many is the most common relationship, and it associates a row from a parent table to multiple rows in a child table. one-to-one requires the child table Primary Key to be… Read More

How to implement a database job queue using SKIP LOCKED

Introduction In this article, we are going to see how we can implement a database job queue using SKIP LOCKED. I decided to write this article while answering this Stack Overflow question asked by Rafael Winterhalter. Since SKIP LOCKED is a lesser-known SQL feature, it’s a good opportunity to show you how to use it and why you should employ it, especially when implementing a job queue task.

How does a relational database execute SQL statements and prepared statements

Introduction In this article, we are going to see how a relational database executes SQL statements and prepared statements.

How to log the database transaction id using MDC (Mapped Diagnostic Context)

Introduction In this article, I’m going to show you how you can log the database transaction id associated with a given SQL statement using the MDC (Mapped Diagnostic Context) feature offered by many logging frameworks. If you are writing data access code, you have to use logging. As I explained in this article, using a JDBC proxy tool like datasource-proxy or p6spy is the best approach to logging SQL statements. With datasource-proxy, you can easily build a JUnit extension to automatically detect N+1 query issues. For more details, check out the db-util… Read More

A beginner’s guide to database multitenancy

Introduction In software terminology, multitenancy is an architectural pattern which allows you to isolate customers even if they are using the same hardware or software components. Multitenancy has become even more attractive with the widespread adoption of cloud computing. A relational database system provides a hierarchy structure of objects which, typically, looks like this: catalog -> schema -> table. In this article, we are going to see how we can use each of these database object structures to accommodate a multitenancy architecture.

A beginner’s guide to Phantom Read anomaly

Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Phantom Read phenomenon.

A beginner’s guide to Non-Repeatable Read anomaly

Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Non-Repeatable Read phenomenon.

A beginner’s guide to Dirty Read anomaly

Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Dirty Read phenomenon.

A beginner’s guide to CDC (Change Data Capture)

Introduction In OLTP (Online Transaction Processing) systems, data is accessed and changed concurrently by multiple transactions and the database changes from one consistent state to another. An OLTP system always shows the latest state of our data, therefore facilitating the development of front-end applications which require near real-time data consistency guarantees. However, an OLTP system is no island, being just a small part of a larger system that encapsulates all data transformation needs required by a given enterprise. When integrating an OLTP system with a Cache, a Data Warehouse or an In-Memory… Read More