Database Integration

Coming Soon

This lesson will teach you how to integrate persistent storage solutions with your chat server. You’ll learn how to:

• Use ETS tables for high-performance in-memory storage
• Integrate with external databases (PostgreSQL, MongoDB)
• Design efficient data models for chat applications
• Implement data migration and versioning strategies
• Build connection pooling and transaction management

What You’ll Build

By the end of this lesson, you’ll have implemented:

• ETS-based caching and session storage
• Database connection pooling and management
• Data access layer with CRUD operations
• Message persistence and history retrieval
• Data migration and schema management

Key Concepts Preview

% ETS table management
-define(USER_TABLE, user_sessions).
-define(MESSAGE_TABLE, message_history).

init_tables() ->
    ets:new(?USER_TABLE, [named_table, public, {read_concurrency, true}]),
    ets:new(?MESSAGE_TABLE, [named_table, public, ordered_set]).

% Database connection
{ok, Conn} = epgsql:connect("localhost", "chat_user", "password", [
    {database, "chat_server"},
    {timeout, 5000}
]).

This lesson builds on the performance optimization from Lesson 23 and prepares you for the distributed systems concepts we’ll explore in Lesson 25.

This lesson is currently under development. Check back soon for the complete content!