Using custom dialect functions

In this recipe, we will show how you can add mappings for database functions, which are not available by default.

How to do it…

1. Create a new class library project named CustomDialectExample.
2. Install the NHibernate and log4net packages using the NuGet Package Manager Console by executing the following command:

   Install-Package NHibernate
   Install-Package log4net
   

3. Create a new class named CustomMsSql2012Dialect using the following code:

   public class CustomMsSq2012Dialect:
     MsSql2012Dialect
   {
     public CustomMsSq2012Dialect()
     {
       RegisterFunction("AddDays",
         new SQLFunctionTemplate(
           NHibernateUtil.DateTime,
           "dateadd(day,?2,?1)"));
       RegisterFunction("AddHours",
         new SQLFunctionTemplate(
           NHibernateUtil.DateTime,
           "dateadd(hour,?2,?1)"));
       RegisterFunction("AddMinutes",
         new SQLFunctionTemplate(
           NHibernateUtil.DateTime,
           "dateadd(minute,?2...