Category: SQL

JavaScript NestJS SQL

API with NestJS #76. Working with transactions using raw SQL queries

This entry is part 76 of 77 in the API with NestJS

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 […]

JavaScript NestJS SQL

API with NestJS #75. Many-to-many relationships using raw SQL queries

This entry is part 75 of 77 in the API with NestJS

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 […]

JavaScript NestJS SQL

API with NestJS #74. Designing many-to-one relationships using raw SQL queries

This entry is part 74 of 77 in the API with NestJS

Learning how to design and implement relationships between tables is a crucial skill for a backend developer. In this article, we continue working with raw SQL queries and learn about many-to-one relationships. You can find the code from this article in this repository. Understanding the many-to-one relationship When creating a many-to-one relationship, a row from […]

NestJS SQL

API with NestJS #69. Database migrations with TypeORM

This entry is part 69 of 77 in the API with NestJS

When working with relational databases, we define the structure of the data rather strictly. For example, we need to specify the format of every table along with fields, relations, indexes, and other structures. By doing that, we also tell the database how to validate the incoming data. It is crucial to think about the structure […]

NestJS SQL

API with NestJS #64. Transactions with PostgreSQL and MikroORM

This entry is part 64 of 77 in the API with NestJS

One of the most important things to care about as a web developer is the integrity of the data. In this article, we learn what a transaction is and how it can help us ensure that our data is correct. The idea behind transactions A transaction is a set of instructions that either happens entirely […]

NestJS SQL

API with NestJS #63. Relationships with PostgreSQL and MikroORM

This entry is part 63 of 77 in the API with NestJS

A significant advantage of SQL databases is handling relationships between various tables. Since, in web applications, entities often relate to each other, designing relationships is a big part of working with SQL databases. In this article, we continue learning MikroORM and use it to form relationships. You can find the code from this article in […]