Transformations.Dapper 2.0.4.1

Transformations.Dapper

Resilient Dapper query wrappers with built-in transient SQL fault detection — drop-in replacements for standard Dapper methods that automatically retry on deadlocks, timeouts, and Azure SQL throttling.

📖 Overview

Transformations.Dapper brings the hardened retry semantics of Transformations.Core directly into your Dapper workflows. Cloud databases regularly drop connections or trigger transient deadlocks — this library automatically identifies retriable SQL error codes and re-executes queries transparently.

🚀 Why Transformations.Dapper?

Instead of manually catching SqlException and writing retry loops everywhere, you swap connection.QueryAsync for connection.QueryWithRetryAsync. The built-in transient fault detector handles the backoff strategy. The result is database code that's both cleaner and more resilient — with no extra ceremony.

📦 Install

<PackageReference Include="Transformations.Dapper" Version="2.0.4.1" />

💡 What's Included

Resilient Async Queries

Swap connection.QueryAsync for connection.QueryWithRetryAsync. Transient SQL faults are detected automatically and retried with exponential backoff.

// 3 retries, 500ms initial delay — doubles each attempt
var users = await connection.QueryWithRetryAsync<User>(
    "SELECT * FROM Users WHERE Status = @Status",
    new { Status = UserStatus.Active },
    retryCount: 3,
    initialDelay: TimeSpan.FromMilliseconds(500));

// Single row — returns null rather than throwing on no result
var user = await connection.QuerySingleOrDefaultWithRetryAsync<User>(
    "SELECT * FROM Users WHERE Id = @Id",
    new { Id = userId });

// Execute (INSERT/UPDATE/DELETE) and scalar
int affected = await connection.ExecuteWithRetryAsync(
    "DELETE FROM Sessions WHERE ExpiredAt < @Now", new { Now = DateTime.UtcNow });

int count = await connection.ExecuteScalarWithRetryAsync<int>(
    "SELECT COUNT(*) FROM Users WHERE Active = 1");

Transient Fault Detection

SqlTransientFaultDetector.IsTransient classifies SQL errors that are safe to retry: deadlocks (1205), timeouts (‑2, 53, 121), Azure throttling (40197, 40501, 40613, 49918), and transport-level errors. Use it in your own catch blocks:

catch (SqlException ex) when (SqlTransientFaultDetector.IsTransient(ex))
{
    logger.LogWarning(ex, "Transient SQL fault on attempt {Attempt}", attempt);
}

SqlParameter Bridge

Converts anonymous or POCO objects to SqlParameter[] — useful when bridging legacy SqlCommand code or when you need explicit SqlDbType control that Dapper's anonymous parameters don't offer.

// From an anonymous object
IReadOnlyList<SqlParameter> sqlParams = SqlParameterBridge.ToSqlParameters(
    new { UserId = 42, Name = "Alice" });

// With explicit SqlDbType overrides
IReadOnlyList<SqlParameter> sqlParams = SqlParameterBridge.ToSqlParameters(
    new { UserId = 42, Bio = longText },
    new Dictionary<string, SqlDbType>
    {
        ["Bio"] = SqlDbType.NVarChar
    });

// NativeAOT / trimmer-safe generic overload
IReadOnlyList<SqlParameter> sqlParams = SqlParameterBridge.ToSqlParameters<MyParams>(myParams);

🛠 API Reference

📦 Dependencies

• Transformations.Core
• Dapper
• Microsoft.Data.SqlClient

License

MIT — Copyright © 2026 opentail.net