HangfireIO/Hangfire · error · MissingMemberException

Property '{type.FullName}.BatchCommand' not found.

Error message

Property '{type.FullName}.BatchCommand' not found.

What it means

MissingMemberException thrown while resolving the BatchCommand property getter on SqlCommandSet via reflection (Instance|Public|NonPublic). The expression that reads the accumulated batch command cannot be compiled because the property is absent on the resolved type.

Source

Thrown at src/Hangfire.SqlServer/SqlCommandSet.cs:94

                _setConnection = SetConnection.GetOrAdd(sqlCommandSetType, static type =>
                {
                    var p = Expression.Parameter(typeof(object));
                    var converted = Expression.Convert(p, type);
                    var connectionParameter = Expression.Parameter(typeof(DbConnection));
                    var connectionProperty = type.GetProperty("Connection", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) ?? throw new MissingMemberException($"Property '{type.FullName}.Connection' not found.");
                    return Expression.Lambda<Action<object, DbConnection>>(Expression.Assign(Expression.Property(converted, connectionProperty), Expression.Convert(connectionParameter, connectionProperty.PropertyType)), p, connectionParameter).Compile();
                });
                _setTransaction = SetTransaction.GetOrAdd(sqlCommandSetType, static type =>
                {
                    var p = Expression.Parameter(typeof(object));
                    var converted = Expression.Convert(p, type);
                    var transactionParameter = Expression.Parameter(typeof(DbTransaction));
                    var transactionProperty = type.GetProperty("Transaction", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) ?? throw new MissingMemberException($"Property '{type.FullName}.Transaction' not found.");
                    return Expression.Lambda<Action<object, DbTransaction>>(Expression.Assign(Expression.Property(converted, transactionProperty), Expression.Convert(transactionParameter, transactionProperty.PropertyType)), p, transactionParameter).Compile();
                });
                var batchCommandProperty = BatchCommandProperty.GetOrAdd(sqlCommandSetType, static type =>
                {
                    return type.GetProperty("BatchCommand", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) ?? throw new MissingMemberException($"Property '{type.FullName}.BatchCommand' not found.");
                });
                _getBatchCommand = GetBatchCommand.GetOrAdd(sqlCommandSetType, type =>
                {
                    var p = Expression.Parameter(typeof(object));
                    var converted = Expression.Convert(p, type);
                    return Expression.Lambda<Func<object, DbCommand>>(Expression.Property(converted, batchCommandProperty), p).Compile();
                });
                _appendMethod = AppendMethod.GetOrAdd(sqlCommandSetType, type =>
                {
                    var p = Expression.Parameter(typeof(object));
                    var converted = Expression.Convert(p, type);
                    var batchCommandParameter = Expression.Parameter(typeof(DbCommand));
                    return Expression.Lambda<Action<object, DbCommand>>(Expression.Call(converted, "Append", null, Expression.Convert(batchCommandParameter, batchCommandProperty.PropertyType)), p, batchCommandParameter).Compile();
                });
                _executeNonQueryMethod = ExecuteNonQueryMethod.GetOrAdd(sqlCommandSetType, static type =>
                {
                    var p = Expression.Parameter(typeof(object));
                    var converted = Expression.Convert(p, type);

View on GitHub (pinned to c236dd0f93)

Solutions

1. Use a SqlClient + Hangfire.SqlServer version pair validated in the Hangfire.SqlServer compatibility matrix.
2. Turn off assembly trimming/obfuscation that strips the property metadata.
3. Open an issue / upgrade Hangfire.SqlServer if the provider legitimately renamed the member.

Example fix

// before
<PackageReference Include="Microsoft.Data.SqlClient" Version="6.0.0-preview" />

// after (use a stable, supported release)
<PackageReference Include="Microsoft.Data.SqlClient" Version="5.2.2" />

static bool HasBatchCommandProperty(Type sqlCommandSetType)
    => sqlCommandSetType.GetProperty("BatchCommand",
        BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) != null;

static bool IsSqlCommandSetUsable(Type type) =>
    type.GetProperty("BatchCommand", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) != null;

When it happens

Trigger: A SqlClient assembly whose SqlCommandSet type does not expose a BatchCommand property under that name; provider renamed the property (e.g. to CommandCollection) or removed it.

Common situations: Provider major-version upgrade that refactored internal batching; trimming; using an unsupported fork of SqlClient.

Related errors

• Property '{type.FullName}.Connection' not found.
• Could not load type 'SqlCommandSet' from assembly '{sqlClien
• Property '{type.FullName}.Transaction' not found.
• SqlCommandSet for {connection.GetType().FullName} is not sup
• The type `{type.FullName}` does not contain a method with si

AI-assisted analysis of HangfireIO/Hangfire@c236dd0f93 (2026-08-13). Data as JSON: /api/errors/81d61b95c62bff2f. Report an issue: GitHub.