Logging

Wire an ILoggerFactory to the DataContextBuilder to capture the executed SQL, parameter values and connection lifecycle messages.

Prerequisites: Connections · Dependency injection · Query reuse.

Overview

Logging is configured per context through the DataContextBuilder: UseLoggerFactory(ILoggerFactory) enables it, and LogSensitiveData(bool) decides whether parameter values may appear in the output. The Use… provider extensions and the options-based DI registration both return the same builder, so logging configuration is provider-independent.

Wiring an ILoggerFactory

Set a factory on the DataContextBuilder; the context creates its loggers in the constructor.

using Microsoft.Extensions.Logging;

using var loggerFactory = LoggerFactory.Create(builder =>
{
    builder.AddConsole().SetMinimumLevel(LogLevel.Debug);
});

var builder = new DataContextBuilder()
    .UseSqlite("app.db")
    .UseLoggerFactory(loggerFactory)
    .LogSensitiveData(false);

using var ctx = builder.CreateDataContext();

The three loggers

Three loggers are created from the factory:

Member	Category	Purpose
Logger	the context type (for example nextorm.sqlite.SqliteDataContext)	connection and command messages. Exposed on IContextEnvironment.
CommandLogger	the QueryCommand type	attached to the commands built by From / From(...). Exposed on IContextEnvironment.
ResultSetEnumeratorLogger	NextORM.Core.ResultSetEnumerator	streaming lifecycle messages (Trace on MoveNext, Debug when opening the connection or disposing the reader). Internal.

LogSensitiveData

LogSensitiveData(bool) controls whether parameter values and the connection string are written. It defaults to false:

• the SQL is logged at Debug as Executing query: {sql};
• with LogSensitiveData(false), a parameterised query additionally logs Use LogSensitiveData to see param values;
• with LogSensitiveData(true), every parameter name and value is logged, and connection creation logs Creating connection with {connStr} instead of just Creating connection.

Turn it on only when the log sink is trusted: parameter values may contain personal data.

Command logging

Buffered terminals (ToList, First, ExecuteScalar, ...) log the command through Logger before executing it. Streaming terminals use ResultSetEnumeratorLogger, which also emits Move next at Trace. Both paths are at Debug, so the log level of the configured factory must allow Debug for anything to appear:

var builder = new DataContextBuilder()
    .UseSqlServer(connectionString)
    .UseLoggerFactory(loggerFactory)
    .LogSensitiveData(true); // includes parameter values in the output

Provider differences

Logging behaves the same across every provider; only the connection type differs. See Connections: provider differences.

See also

• Connections
• Dependency injection
• Query reuse: plan cache and Prepare
• Documentation index

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Source: src/nextorm.core/DI/DataContextBuilder.cs:20 (UseLoggerFactory).