How to log SQL calls with NHibernate to the console of Visual Studio?

Question

I have the following configuration file for NHibernate:

<?xml version="1.0" encoding="utf-8" ?> <hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">   <session-factory>     <property name="connection.connection_string">Server=.\SQLEXPRESS;Database=mydb;Integrated Security=True;</property>     <property name="dialect">NHibernate.Dialect.MsSql2005Dialect</property>     <property name="connection.provider">NHibernate.Connection.DriverConnectionProvider</property>     <property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>     <property name="connection.release_mode">auto</property>     <property name="adonet.batch_size">500</property>      <property name="show_sql">true</property>    </session-factory> </hibernate-configuration> 

But the SQL doesn't show in the output window of Visual Studio. Is it mandatory to install log4net? Or should show_sql work alone?

Answer 1

To show the SQL in the output window of Visual Studio, configure log4net to use TraceAppender in your log4net config. This:

<appender name="DebugSQL" type="log4net.Appender.TraceAppender">     <layout type="log4net.Layout.PatternLayout">         <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />     </layout> </appender> 

Then this:

<logger name="NHibernate.SQL" additivity="false">     <level value="DEBUG" />     <appender-ref ref="DebugSQL" /> </logger> 

EDIT: I can't seem to format this correctly here. See this link for code example

Answer 2

For those who prefer code rather than configuration, the following snippet will create the appropriate NH logger with a simple console appender.

var hierarchy = (Hierarchy) LogManager.GetRepository(); var logger = (Logger) hierarchy.GetLogger("NHibernate.SQL"); logger.AddAppender(new ConsoleAppender {Layout = new SimpleLayout()}); hierarchy.Configured = true;