Testcontainers Database Integration Testing
Introduction In this article, we are going to see how we can use Testcontainers for database integration testing. If you are still using HSQLDB or H2 to test your Spring Boot application that runs on Oracle, SQL Server, PostgreSQL or MySQL in production, then you are better off switching to Testcontainers.
Maximum number of database connections
Introduction Have you ever wondered what the maximum number of database connections provided by a given RDBMS is? In this article, we are going to see what limits the number of database connections, no matter if you’re using Oracle, SQL Server, PostgreSQL, or MySQL.
Merge Join Algorithm
Introduction In this article, we are going to see how the Merge Join Algorithm, also known as Sort-Merge Join, works and when it’s suitable for a relational database system to employ it in order to execute an SQL JOIN query.
Hash Join Algorithm
Introduction In this article, we are going to see how the Hash Join Algorithm works and when it’s suitable for a relational database system to employ it in order to execute an SQL JOIN query.
Nested Loop Join Algorithm
Introduction In this article, we are going to see how the Nested Loop Join Algorithm works and when it’s suitable for a relational database system to employ it in order to execute an SQL JOIN query.
Flyway Database Schema Migrations
Introduction In this article, I’m going to explain how Flyway works and how you can use it to run automated database schema migrations using incremental SQL migration scripts. Flyway is an open-source project created by Axel Fontaine and later acquired by Red Gate. The database migrations can be defined either as SQL scripts or JDBC-based classes.
How does the 2PL (Two-Phase Locking) algorithm work
Introduction The 2PL (Two-Phase Locking) algorithm is one of the oldest concurrency control mechanisms used by relational database systems to guarantee data integrity. In this article, I’m going to explain how the 2PL algorithm works and how you can implement it in any programming language.
PostgreSQL trigger consistency check
Introduction In this article, we are going to see how to implement a non-trivial consistency check using a PostgreSQL INSERT and UPDATE trigger. By using a database trigger after executing an INSERT or UPDATE, we can ensure that the sum of salaries in a given department does not exceed the maximum budget allocated for the given department.
A beginner’s guide to database deadlock
Introduction In this article, we are going to see how a deadlock can occur in a relational database system, and how Oracle, SQL Server, PostgreSQL, or MySQL recover from a deadlock situation.
Hibernate database schema multitenancy
Introduction As I explained in this article, multitenancy is an architectural pattern which allows you to isolate customers even if they are using the same hardware or software components. There are multiple ways you can achieve multitenancy, and in this article, we are going to see how you can implement a multitenancy architecture using the database schema as the unit of isolation.
