🏢 Google Internal Employee & Project Management System (PostgreSQL)

A complete PostgreSQL project to manage employees, projects, performance, and tools — modeled after Google-like enterprise systems.

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📑 Table of Contents

• 📦 Features
• 🧱 Schema Overview
• 🧩 ER Diagram
• 📘 PostgreSQL Tutorial
• 🗂️ SQL Practice Tasks
• 🚀 Setup Instructions
• 🧪 Sample Queries
• 📄 License

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📦 Features

• ✅ 12 PostgreSQL tables with rich relationships
• ✅ 20 sample rows per table
• ✅ Real-world data (projects, salaries, tools, etc.)
• ✅ Views, triggers, functions, CTEs, and window functions
• ✅ Perfect for advanced SQL practice & interview prep

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🧱 Schema Overview

• employees, departments, salaries
• projects, employee_projects, performance_reviews
• products, tool_usage_logs, access_rights, audit_logs
• locations, employee_locations

Designed for enterprise-level scale and analytics.

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Relationship ER

Relationship	Type
departments.head_id → employees.employee_id	One-to-One
employees.dept_id → departments.dept_id	Many-to-One
employees.salary_id → salaries.salary_id	Many-to-One
employee_projects.employee_id → employees.employee_id	Many-to-One
employee_projects.project_id → projects.project_id	Many-to-One
performance_reviews.employee_id → employees.employee_id	Many-to-One
performance_reviews.reviewer_id → employees.employee_id	Many-to-One
products.dept_id → departments.dept_id	Many-to-One
products.product_manager_id → employees.employee_id	Many-to-One
employee_locations.employee_id → employees.employee_id	Many-to-One
employee_locations.location_id → locations.location_id	Many-to-One
tool_usage_logs.employee_id → employees.employee_id	Many-to-One
access_rights.employee_id → employees.employee_id	Many-to-One
audit_logs.employee_id → employees.employee_id	Many-to-One

Complex JOINs example pg-admin4

window function example pg-admin4

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🧩 ER Diagram

🖼️ ER diagram available in:

• Visual layout included in documentation

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📘 PostgreSQL Tutorial

🔰 Getting Started

sudo apt install postgresql
sudo -u postgres psql