In this series, we’ve often had to filter the records in our database. We can achieve that with a simple WHERE clause.
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SELECT * FROM posts WHERE author_id = 1 |
In this article, we go through different use cases of more advanced filtering. We achieve it by using the WHERE keyword with subqueries. EXISTS In some of the previous parts of this series, […]
It is very common to implement a feature of searching through the contents of the database. In one of the previous articles, we learned how to implement it in a simple way using pattern matching. Today we take it a step further and learn about the data types explicitly designed for full-text search. Text Search […]
As our database grows, we need to put more and more emphasis on performance. A popular approach to dealing with this problem is by implementing indexes. In this article, we look into doing that with raw SQL in a project that does not use ORM. Introducing indexes So far, in this series, we’ve created a […]
Removing entities is a very common feature in a lot of web applications. The most straightforward way of achieving it is permanently deleting rows from the database. In this article, we implement soft deletes that only mark records as deleted. You can find the code from this article in this repository. The idea behind soft […]
A significant thing to realize when developing a REST API is that HTTP methods are a matter of convention. For example, in theory, we could delete entities with the POST method. However, our job is to create an API that is consistent with the REST standard and works predictably. Updating existing rows in the database […]
The possibility of searching through the contents of the database is a very common feature. There are great solutions built with that use case in mind, such as Elasticsearch. Even though that’s the case, PostgreSQL also has the functionality of matching a given string pattern. In this article, we explore what PostgreSQL offers and use […]
So far, we’ve been mostly writing SQL queries that either store or retrieve the data from the database. Besides that, we can rely on PostgreSQL to process the data and get the computed results. By doing that, we can learn more about the rows in our tables. In this article, we look into how we […]
So far, we have returned the full content of our tables. However, as our database grows, this might prove not to be the best approach in terms of performance. A popular solution is to serve the data in chunks by presenting multiple pages or implementing infinite scrolling. In this article, we implement its back-end aspect […]
One of the challenges when working with databases is keeping the integrity of the data. In this article, we learn how to deal with it using transactions. A transaction can contain multiple different instructions. The crucial thing about a transaction is that it either runs entirely or doesn’t run at all. Let’s revisit the most common […]
Designing relationships between tables is one of the crucial parts of working with databases. In this article, we look into a more complex relationship called many-to-many. You can find the code from this article in this repository. The many-to-many relationship A many-to-many relationship happens when many records in one table relate to many records in another […]
