Database Configuration

GeoIDs.jl uses PostgreSQL with the PostGIS extension to store and manage GEOID sets. The package provides flexible configuration options through environment variables.

Note: If you need to install and set up PostgreSQL first, see our PostgreSQL Setup Guide.

Environment Variables

You can customize the database connection using these environment variables:

Setting Environment Variables

Within Julia

You can set environment variables before loading the package:

# Set database configuration
ENV["GEOIDS_DB_NAME"] = "my_census_db"
ENV["GEOIDS_DB_HOST"] = "db.example.com"
ENV["GEOIDS_DB_PORT"] = "5433"
ENV["GEOIDS_DB_USER"] = "census_user"
ENV["GEOIDS_DB_PASSWORD"] = "secure_password"

# Load package
using GeoIDs

Command Line

You can set environment variables when running your script:

GEOIDS_DB_NAME=my_census_db GEOIDS_DB_HOST=db.example.com julia my_script.jl

Configuration File

For a more permanent solution, you can add configuration to your .bashrc, .zshrc, or equivalent:

# Add to your .bashrc or .zshrc
export GEOIDS_DB_NAME=my_census_db
export GEOIDS_DB_HOST=db.example.com
export GEOIDS_DB_USER=census_user

Database Setup

GeoIDs.jl requires these database tables:

1. census.counties - Table containing county information with GEOID and geometry
2. census.geoid_sets - Table for GEOID set metadata (created automatically)
3. census.geoid_set_members - Table for GEOID set members (created automatically)
4. census.geoid_set_changes - Table for tracking changes (created automatically)

All required tables are created automatically when you run the initialize_database() function. This function:

1. Creates the census schema if it doesn't exist
2. Enables the PostGIS extension if needed
3. Downloads and extracts the U.S. Census TIGER/Line county shapefile
4. Creates the census.counties table with proper schema
5. Loads county data with GEOIDs and geometries
6. Sets up the GEOID set management tables

Required Schema

The census.counties table must have the following schema:

CREATE TABLE census.counties (
    geoid VARCHAR(5) PRIMARY KEY,
    name VARCHAR(100),
    stusps VARCHAR(2),  -- State postal code
    geom GEOMETRY(MultiPolygon, 4269)  -- County geometry
    -- Other fields can vary
);

This table is automatically created and populated when you run initialize_database().