Raw SQL Vs Dapper

Introduction

Developers have several options when interacting with a database in a .NET application. Two of the most popular ones are Raw SQL and Dapper. This article will compare and contrast these two approaches with clear examples of their use cases, advantages, and drawbacks.

Raw SQL

Raw SQL is simply a string of SQL commands a developer sends to a database to perform various operations such as querying, inserting, updating or deleting data. It's the traditional way of interacting with a database from a .NET application, which is still widely used today.

Here's an example of a raw SQL query that retrieves all the employees whose salaries are above $100,000 from an "Employees" table:

SELECT * FROM Employees WHERE Salary > 100000;

Advantages of Raw SQL

• Flexibility- Raw SQL gives developers complete control over the SQL commands they send to the database. They can optimize queries for performance, use advanced SQL features, and write complex queries that are difficult or impossible to express in an ORM.
• Performance- Raw SQL queries can be faster than ORMs for complex queries or large datasets since object mapping has no overhead.
• Familiarity- Developers already familiar with SQL can easily use raw SQL.

Drawbacks of Raw SQL

• Maintenance- Raw SQL queries can be harder to maintain as the codebase grows and changes, and queries can become scattered throughout the application.
• Security- Raw SQL can introduce security vulnerabilities if user input is not properly sanitized and validated, leading to SQL injection attacks.

Dapper

Dapper is a lightweight ORM that extends the functionality of raw SQL by providing an easy-to-use mapping mechanism between SQL results and .NET objects. It's a popular choice among developers because it balances raw SQL's flexibility and an ORM's convenience.

Here's an example of a Dapper query that retrieves all the employees whose salaries are above $100,000 from an "Employees" table:

var highSalaryEmployees = connection.Query<Employee>(
    "SELECT * FROM Employees WHERE Salary > @salaryThreshold", 
    new { salaryThreshold = 100000 });

Advantages of Dapper

• Simplified data access- Dapper eliminates the need to write boilerplate ADO.NET code and provides a simple API for executing SQL commands and mapping results to objects.
• Security- Dapper automatically parameterizes SQL queries, which helps prevent SQL injection attacks.
• Performance- Dapper's lightweight implementation and object mapping capability can lead to faster code execution.

Drawbacks of Dapper

• Limited functionality- Dapper does not provide advanced query building and manipulation capabilities like ORMs such as Entity Framework or NHibernate.
• Learning curve- Developers new to Dapper may need to learn its syntax and features.

Conclusion

Raw SQL and Dapper are two viable options for interacting with a database in a .NET application, each with advantages and drawbacks. Dapper simplifies data access and improves security, but it has a limited feature set and may require a learning curve. Raw SQL provides complete control and flexibility, but maintaining and introducing security vulnerabilities can be harder.

Ultimately, the choice between raw SQL and Dapper depends on the specific needs of the project and the developer's preferences and expertise.