🗺️ Geolocation Project with PostgreSQL 16 + PostGIS 3

Overview

This project uses PostgreSQL 16 with the PostGIS 3 extension to handle spatial and geolocation data, such as coordinates, areas, distances, and shapes. It is suitable for use cases like:

• Tracking user or asset locations
• Geo-fencing and area-based services
• Location-based search (e.g. "nearest X")
• Mapping and GIS applications
• Spatial analytics

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📦 Requirements

• Ubuntu 22.04 or newer
• PostgreSQL 16
• PostGIS 3 extension
• Optional: Backend framework (Laravel, Node.js, Django, etc.)

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🛠️ Installation Guide

Step 1: Add PostgreSQL APT Repository

echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" | sudo tee /etc/apt/sources.list.d/pgdg.list

Step 2: Import PostgreSQL GPG Key

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -

Step 3: Update Package List

sudo apt update

Step 4: Install PostgreSQL 16 with PostGIS 3

sudo apt install postgresql-16-postgis-3

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📂 Create a Spatial Database

Step 1: Create Database & User (optional)

sudo -u postgres psql

-- Inside psql shell:
CREATE DATABASE geo_db;
\c geo_db
CREATE EXTENSION postgis;
CREATE EXTENSION postgis_topology;

✅ postgis adds geometry types & functions ✅ postgis_topology adds topological support (optional)

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🔍 Example Queries

-- Create a table with a geometry column
CREATE TABLE locations (
    id SERIAL PRIMARY KEY,
    name VARCHAR,
    geom GEOGRAPHY(POINT, 4326) -- Latitude & Longitude in WGS84
);

-- Insert a sample point (longitude, latitude)
INSERT INTO locations (name, geom)
VALUES ('Test Location', ST_GeogFromText('SRID=4326;POINT(51.389 35.6892)'));

-- Find all locations within 10km of a given point
SELECT *
FROM locations
WHERE ST_DWithin(
    geom,
    ST_MakePoint(51.4, 35.7)::geography,
    10000 -- meters
);

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🧪 Useful Commands

# Connect to database
psql -U postgres -d geo_db

# List installed extensions
\dx

# List geometry columns
SELECT * FROM geometry_columns;

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🌍 Coordinate System Used

• SRID 4326 (WGS84)

  • Latitude/Longitude in degrees
  • Globally recognized standard used by GPS

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🧠 Tips

• Always specify SRID=4326 when working with geographic coordinates.
• Use GEOGRAPHY type for great-circle distance queries (meters).
• Use GEOMETRY type if you need planar calculations (x/y).

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🔒 Security Note

Never expose your PostgreSQL server publicly without proper authentication, SSL, and firewall settings.

sudo apt install postgresql-16-postgis-3