Building a Full-Text Search Engine Inside .NET MAUI with SQLite's FTS5 Extension

🔎 Building a Full-Text Search Engine Inside .NET MAUI with SQLite FTS5

using Shaunebu.Data.SQLite 🗄️✨

Full-text search is one of those features that instantly elevates an app from usable to professional. In offline-first .NET MAUI apps, implementing fast, ranked, and scalable search is often a challenge—especially if you want to avoid cloud dependencies or heavy ORMs.

In this guide, we’ll build a full-text search engine inside a .NET MAUI application using:

• 🧠 SQLite FTS5 for blazing-fast full-text indexing
• 🗄️ Shaunebu.Data.SQLite for clean, thread-safe, fluent data access
• ⚡ Fully async, cross-platform, and production-ready architecture

🚀 Why Use Full-Text Search in .NET MAUI?

Common approaches like LIKE '%query%' or in-memory filtering break down quickly as data grows.

❌ Traditional Search Problems

✅ What FTS5 Gives You

• Tokenized search
• Prefix & phrase matching
• Relevance ranking (BM25)
• Extremely fast queries
• Works 100% offline

🧩 Why Shaunebu.Data.SQLite?

Shaunebu.Data.SQLite provides a lightweight, thread-safe SQLite manager designed specifically for .NET & .NET MAUI apps.

Key advantages:

• 🧵 Thread-safe singleton per database
• ⚡ Async CRUD & batch operations
• 🧩 Fluent LINQ-style queries
• 🛠 Built-in table management
• 📝 Optional logging via ILogger

This makes it an ideal foundation for building an embedded search engine.

📦 Installation

PM> Install-Package Shaunebu.Data.SQLite

Compatible with:

✅ .NET 8+

✅ .NET MAUI 8+

⚙️ Setup

The manager uses a singleton per database file, ensuring thread safety.

🗄️ Step 1: Define the Searchable Model

Create the base table:

🔍 Step 2: Create the FTS5 Virtual Table FTS tables are created via raw SQL, which Shaunebu.Data.SQLite fully supports.

🔄 Step 3: Keep the Index in Sync (Triggers)

Now your FTS index updates automatically—no manual syncing required.

🧠 Step 4: Insert Data (Batch-Friendly)

Batch inserts are wrapped in transactions automatically ⚡

🔎 Step 5: Perform Full-Text Search

Example Queries

maui
"full text search"
sqlite*

🎨 Step 6: Bind Search to .NET MAUI UI

🧩 ViewModel Example

⚡ Performance Best Practices

• ✅ Index only searchable fields
• ✅ Limit results (LIMIT)
• ✅ Prefer prefix search (term*)
• ❌ Avoid leading wildcards (*term)
• ❌ Don’t index large binary text

🧪 Ideal Use Cases

🏁 Conclusion

By combining SQLite FTS5 with Shaunebu.Data.SQLite, you can build a powerful, offline-first full-text search engine directly inside your .NET MAUI app—without cloud services, heavy ORMs, or complex infrastructure.

What you gain:

• 🚀 High-performance search
• 🧠 Relevance ranking
• 📦 Offline reliability
• 🧩 Clean, fluent data access
• 🧵 Thread-safe architecture

If your MAUI app needs serious search capabilities, this approach is fast, elegant, and production-ready.

🔗 References https://www.sqlite.org/fts5.html

https://learn.microsoft.com/dotnet/maui

https://www.nuget.org/packages/Shaunebu.Data.SQLite

https://github.com/praeclarum/sqlite-net

Happy coding! 🚀🗄️