The internet is filled with vast amounts of valuable data. However, much of the information isn’t available in a structured format we can download and use. To handle that, we can use web scraping. Web scraping is a process of extracting data from websites that don’t provide it in a structured format out of the […]
With NestJS 11, the framework now comes with Express 5 by default. While the update is mostly painless, there are some breaking changes to consider. In this article, we go through what new features Express 5 brings to the table and how it affects NestJS. Installing Express 5 Express 4 was released in April 2014. […]
Artificial Intelligence (AI) is a broad and complex field, and getting started can be overwhelming. In this article, we learn how Machine Learning is related to AI and train our first model to determine whether a given piece of text is a spam message. Artificial Intelligence and Machine Learning Artificial Intelligence focuses on developing systems […]
When using PostgreSQL with PostGIS, we can do various operations using polygons. In this article, we learn how to do that both through raw SQL queries and the Drizzle ORM. Storing polygons using the Drizzle ORM To store polygons using the Drizzle ORM, we use a custom data type and the areas table. database-schema.ts
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import { serial, text, pgTable } from 'drizzle-orm/pg-core'; import { customType } from 'drizzle-orm/pg-core'; import { Geometry } from 'wkx'; type Coordinate = [number, number]; interface GeoJson { type: string; coordinates: Coordinate[][]; } const polygon = customType<{ data: Coordinate[][]; driverData: string }>({ dataType() { return 'geometry(Polygon, 4326)'; }, toDriver(coordinates: Coordinate[][]): string { return JSON.stringify({ type: 'Polygon', coordinates, }); }, fromDriver(data: string) { const geoJson = Geometry.parse( Buffer.from(data, 'hex'), ).toGeoJSON() as GeoJson; return geoJson.coordinates; }, }); export const areas = pgTable('areas', { id: serial().primaryKey(), name: text().notNull(), polygon: polygon('polygon').notNull(), }); export const databaseSchema = { areas, }; |
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PostgreSQL, together with PostGIS, allows us to store various types of geographical data. Besides working with simple coordinates, we can also store entire areas in the form of polygons. In this article, we learn how to handle polygons with PostgreSQL and the Drizzle ORM. While Drizzle ORM does not support it out of the box, we […]
PostgreSQL provides many options for working with geographical data, especially with the PostGIS extension. In this article, we’ll explore how to calculate the distance between two coordinates and how to identify locations within a specific radius. If you want to check out the basics of storing coordinates in PostgreSQL with the Drizzle ORM, check out […]
Many applications rely on geographical data to calculate distances and track locations. PostgreSQL offers several ways to store geospatial data, each designed with different goals. In this article, we learn how to store coordinates when working with PostgreSQL and the Drizzle ORM. Latitude and longitude A coordinate consists of two numbers that pinpoint a location […]
When we execute an SQL query, PostgreSQL follows a process that consists of multiple steps. First, it parses the SQL statement, checking for syntax errors. Next, it analyzes whether the tables and columns used in the query exist. Then, it plans the instructions necessary to achieve the desired result. Finally, it executes the instructions based on […]
As our application grows, it gets increasingly important to create a file structure that’s easy to maintain. Also, if we care about it from the start, it is easier to achieve. In this article, we learn how to organize the database schema when working with the Drizzle ORM and NestJS. Handling column names When working […]
Searching through text documents is a very common feature in many web applications. In this article, we learn how to implement it using pattern matching using the Drizzle ORM, PostgreSQL, and NestJS. Pattern matching with LIKE and ILIKE With pattern matching, we can determine if a given piece of text matches a particular pattern. To […]
