MSSQL IO #

A Flutter plugin for connecting to Microsoft SQL Server. Supports Android, iOS, Windows, macOS, Linux, and Web.

Features #

• Direct FFI access for high performance
• Parameterized queries to prevent SQL injection
• Transaction support (BEGIN, COMMIT, ROLLBACK)
• Bulk insert operations
• Cross-platform compatibility

Installation #

dependencies:
  mssql_io: ^0.0.2

flutter pub get

Setup #

Mobile (Android & iOS) #

# Android
cd android && ./build_freetds.sh

# iOS (requires macOS)
cd ios && ./build_freetds.sh

First build takes 10-15 minutes (builds FreeTDS library). Subsequent builds are fast.

Desktop #

macOS:

brew install freetds

Linux:

sudo apt-get install freetds-dev

Windows:

vcpkg install freetds:x64-windows

Web #

Web applications require a backend API server to proxy SQL Server connections (for security).

// Configure web API endpoint
MssqlIoWeb.getInstance().configure(
  apiBaseUrl: 'https://your-api.com/sql',
  authToken: 'your-auth-token',
);

// Execute queries via API
final result = await MssqlIoWeb.getInstance().executeQuery(
  'SELECT * FROM Users',
);

Note: Never expose database credentials in web applications. Always use a secure backend API.

Usage #

import 'package:mssql_io/mssql_io.dart';

// Connect
final request = MssqlConnection.getInstance();
await request.connect(
  host: '192.168.1.100',
  databaseName: 'MyDB',
  username: 'sa',
  password: 'Password123',
);

// Query
final result = await request.getData('SELECT * FROM Users');
for (final row in result.rows) {
  print('User: ${row['Name']}');
}

// Disconnect
await request.disconnect();

Common Examples #

Parameterized Queries (Prevents SQL Injection) #

final result = await request.getDataWithParams(
  'SELECT * FROM Users WHERE Age > @age',
  [SqlParameter(name: 'age', value: 18)],
);

Insert/Update/Delete #

final rows = await request.writeDataWithParams(
  'INSERT INTO Users (Name, Email) VALUES (@name, @email)',
  [
    SqlParameter(name: 'name', value: 'Alice'),
    SqlParameter(name: 'email', value: 'alice@example.com'),
  ],
);
print('Inserted $rows rows');

Transactions #

await request.beginTransaction();
try {
  await request.writeData('INSERT INTO Orders VALUES (1, 99.99)');
  await request.writeData('UPDATE Inventory SET Stock = Stock - 1');
  await request.commit();
} catch (e) {
  await request.rollback();
}

Bulk Insert #

final rows = List.generate(1000, (i) => {'Name': 'User$i', 'Age': 20 + i});
await request.bulkInsert('Users', rows, batchSize: 500);

API #

Main Methods:

• connect() - Connect to SQL Server
• getData() - Execute SELECT query
• getDataWithParams() - Secure parameterized query
• writeData() - Execute INSERT/UPDATE/DELETE
• writeDataWithParams() - Secure parameterized write
• beginTransaction(), commit(), rollback() - Transactions
• bulkInsert() - Batch insert rows
• disconnect() - Close connection

Result Object:

QueryResult {
  columns: ['Id', 'Name', 'Age'],
  rows: [{'Id': 1, 'Name': 'Alice', 'Age': 25}],
  affectedRows: 0
}

Security #

Always use parameterized queries to prevent SQL injection:

// Good - Safe
await request.getDataWithParams(
  'SELECT * FROM Users WHERE Name = @name',
  [SqlParameter(name: 'name', value: userInput)],
);

// Bad - SQL Injection Risk!
await request.getData("SELECT * FROM Users WHERE Name = '$userInput'");

Troubleshooting #

Can't connect?

• Check SQL Server is running on port 1433
• Verify firewall allows connections
• Test: telnet your-server 1433

Library not found?

• Run ./build_freetds.sh in android/ or ios/ folder
• Desktop: Install FreeTDS (brew install freetds on macOS)

Build errors?

flutter clean
flutter pub get
flutter build apk  # or ios

Author #

Farhan Sadik Galib - farhansadikgalib.com