SQL Server Course Labs — From Fundamentals to Business Reporting

This repository is a structured SQL Server learning portfolio that documents my end-to-end progression in T-SQL:

• Database setup and schema design (DDL)
• Data types, keys, and constraints
• Querying, filtering, and joins
• Procedural SQL with stored procedures
• Advanced set operators and subquery patterns
• Automation with cursors and triggers
• Multi-level business reporting with window functions and executive KPIs

The labs are intentionally organized like a mini curriculum so a reviewer can quickly understand both technical depth and learning discipline.

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Tech Stack

• Database: Microsoft SQL Server
• Language: T-SQL
• Datasets:
  • BikeStores (retail sales/inventory/staff operations)
  • UniversityDB (academic departments/courses/instructors)

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Portfolio Goals

This repo is designed to show that I can:

1. Build and manage relational database structures.
2. Write clean, readable, and testable SQL scripts.
3. Move from basic queries to production-style reporting logic.
4. Solve business problems (sales performance, churn risk, ranking, YTD trends) using SQL only.

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Repository Roadmap

00-Database-Setup
01-Introduction-DDL
02-DataTypes-Constraints
03-Basic-Queries-Filtering
04-Joins-Relations
05-Stored-Procedures
06-Advanced-Set-Operators
07-Cursors-and-Triggers
08-Complex-Reporting

00 — Database Setup

Environment initialization scripts for the two training databases.

• BikeStores object creation, data load, and cleanup
• UniversityDB creation + practice queries

01 — Introduction to DDL

Core schema operations and table lifecycle practices.

• CREATE/DROP DATABASE
• CREATE/ALTER TABLE
• IDENTITY, temporary tables

02 — Data Types & Constraints

Data quality and integrity fundamentals.

• Numeric/date/string type strategy
• PRIMARY KEY, FOREIGN KEY, CHECK, DEFAULT
• Computed columns and SELECT INTO

03 — Basic Queries & Filtering

Query foundation and data slicing patterns.

• SELECT, TOP, ORDER BY
• WHERE, LIKE, BETWEEN, conditional filtering

04 — Joins & Relations

Relational thinking and multi-table analysis.

• INNER, LEFT, RIGHT, FULL OUTER JOIN
• aliasing and readable query composition

05 — Stored Procedures

Reusable SQL programming patterns.

• creating procedures
• input/output parameters
• variables and IF...ELSE control flow

06 — Advanced Set Operators

Comparative querying and result-set logic.

• UNION, INTERSECT, EXCEPT
• EXISTS, ANY, ALL

07 — Cursors & Triggers

Database-side automation and event-driven behavior.

• cursor lifecycle and controlled row-by-row operations
• trigger-based validation/auditing scenarios

08 — Complex Reporting (Showcase Module)

This module represents the most business-oriented part of the repo.

• Level 1: summary reporting and store/brand performance
• Level 2: window functions for YTD totals and ranking logic
• Level 3: executive dashboard query for churn-risk detection (including CTE-driven customer segmentation)

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How to Run (Recommended Order)

1. Execute scripts in 00-Database-Setup/ first.
2. Continue folder-by-folder from 01 to 08.
3. Treat each script as a focused lab and run sections incrementally.

Tip: For review/demo sessions, start with 08-Complex-Reporting after setup to quickly show advanced capability.

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What a Reviewer Can Expect

• Clear progression from beginner concepts to advanced analysis
• Practical SQL patterns that mirror real-world business requests
• Evidence of problem-solving beyond syntax memorization
• A reusable set of scripts suitable for interview walkthroughs

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Next Professionalization Steps (Planned)

• Add inline “problem statement → solution” headers to each lab file
• Add expected output snapshots for key reports
• Add indexing/performance notes (SET STATISTICS IO/TIME) for advanced queries
• Add transaction/error-handling labs (TRY...CATCH, rollback strategy)

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Author

Mert Aydın
SQL Server / Database Management Systems Practice Repository (2026)