Requirements: SQL Query Builder

1. Functional Requirements

These are the core features the system must perform.

a. User Interface for Query Building

• Allow users to select tables and fields.
• Support drag-and-drop or form-based selection for ease of use.

b. Support for Basic SQL Clauses

• SELECT, FROM, WHERE, ORDER BY, GROUP BY, HAVING.
• Users can add multiple conditions and logical operators (AND, OR, NOT).

c. Join Support

• Ability to perform INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.
• Users should be able to select join type and join condition visually or through input.

d. Query Preview

• Display the generated SQL query in a text area before execution.
• Option to edit raw SQL if advanced users want to.

e. Query Execution

• Execute the query on a connected database and return results in tabular form.
• Show errors clearly if the query fails.

f. Save & Load Queries

• Allow users to save frequently used queries.
• Load saved queries for re-use and editing.

g. Query Validation

• Validate query syntax before execution.
• Highlight potential issues like missing fields, ambiguous joins, or wrong data types.

h. Export Results

• Support export of query results to CSV, Excel, or JSON formats.

2. Non-Functional Requirements

These describe how well the system should perform.

a. Usability

• Simple and intuitive interface for both technical and non-technical users.
• Tooltips and help icons to assist in query building.

b. Performance

• Queries should execute quickly for large datasets (depending on the DB engine).
• UI must remain responsive during long query runs.

c. Scalability

• Support multiple users, sessions, and large database schemas.
• Handle complex queries involving multiple tables.

d. Security

• Proper authentication before access.
• Limit access to database schemas and tables based on user roles.
• Prevent SQL injection, even when editing raw SQL.

e. Compatibility

• Support for multiple database engines (e.g., MySQL, PostgreSQL, SQL Server, Oracle).
• Use a database-agnostic query builder where possible.

3. Optional / Advanced Requirements

These can be discussed as system extensions or for bonus feature sets:

• Syntax highlighting for raw SQL editing.
• Real-time query performance stats (execution time, rows returned).
• Visual ERD (Entity Relationship Diagram) support.
• AI-assisted query suggestions.

How to Explain in Class:

• Start with user goals: “What does the user want to achieve?” → Build and run queries easily.
• Separate Functional vs Non-Functional: Helps students learn requirement types clearly.
• Use simple scenarios: Like “HR wants all employees with salary > 50000 grouped by department.”