Question

I need to dynamically add named queries to the NHibernate configuration object. The search engines return few hits referencing NamedSQLQueryDefinition or NamedQueryDefinition. Below is what I’m attempting to do. I don’t know what to provide to the NamedSQLQueryDefinition constructor to successfully create a query. Can anyone provide a sample of how to create a new NamedSQLQueryDefinition the right way? Thanks!!

Session initializer:

    private static ISessionFactory CreateSessionFactory()
    {
        var configuration = new Configuration();

        return Fluently.Configure(configuration.Configure())
            .ExposeConfiguration(AddQueries)
            .Mappings(m => m.FluentMappings.AddFromAssemblyOf<Program>())
            .Mappings(m => m.HbmMappings.AddFromAssemblyOf<Program>())
            .BuildConfiguration()
            .BuildSessionFactory();
    }

The AddQueries would look something like this:

    private static void AddQueries(Configuration cfg)
    {
        var nameQuery = new NamedSQLQueryDefinition("exec pr_GETCustomer ?", ...)

        cfg.NamedSQLQueries.Add("pr_GETCustomer", nameQuery);
        var cust = cfg.GetClassMapping(typeof (Customer));

        cust.LoaderName = "pr_GETCustomer";
    }

PS: I’m trying this route because Fluent NHibernate does not implement a way to configuring the loader & sql-query elements from the hbm file.

Answer 1

The AddQueries method would be implemented as follows below to “fix” the Fluent NHibernate lack of Loader support. The trick is to properly set up the INativeSQLQueryReturn[] value to contain the mapping from the table columns to the entity properties. It should mimic the contents of the return element of sql-query in the HBM file where the class (with namespace) and property mappings are defined (see XML below). Thanks to @jimbobmcgee for getting me started in this direction!

private static void AddQueries(Configuration cfg)
{
    var namedQuery = new NamedSQLQueryDefinition(
        "exec dbo.pr_GETCustomers @CustomerID=?",
        new INativeSQLQueryReturn[]
            {
                new NativeSQLQueryRootReturn(
                    "Customers",
                    "VehicleInfo.Entities.Customers",
                    new Dictionary<string, string[]>
                        {
                                    {"CustomerID", new[] {"CustomerID"}},
                                    {"CompanyName", new[] {"CompanyName"}}
                    },
                    LockMode.Read)
            },
        new List<string> { "dbo.Customers" },
        true,
        null,
        15,
        1000,
        FlushMode.Auto,
        CacheMode.Normal,
        false,
        "",
        null,
        true);

    cfg.NamedSQLQueries.Add("pr_GETCustomers", namedQuery);
    var cust = cfg.GetClassMapping(typeof(Customers));

    cust.LoaderName = "pr_GETCustomers";
}

Sample HBM file that does the same thing:

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
    default-access="property" auto-import="true" 
    default-cascade="none" default-lazy="true">
    <class xmlns="urn:nhibernate-mapping-2.2"
        mutable="true" name="VehicleInfo.Entities.Customers, VehicleInfo, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" table="Customers">
        <id name="CustomerID" type="System.String, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
            <column name="CustomerID" />
            <generator class="assigned" />
        </id>

        <property name="CompanyName" type="System.String, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
            <column name="CompanyName" />
        </property>

        <loader query-ref="pr_GETCustomers"/>

        <sql-insert callable="true" check="none">exec dbo.pr_INSERTCustomers @CompanyName=?, @CustomerID=?</sql-insert>
        <sql-update callable="true" check="none">exec dbo.pr_UPDATECustomers @CompanyName=?, @CustomerID=?</sql-update>
        <sql-delete callable="true" check="none">exec dbo.pr_DELETECustomers @CustomerID=?</sql-delete>
    </class>
    <sql-query name="pr_GETCustomers">
        <return alias="cust" class="VehicleInfo.Entities.Customers, VehicleInfo, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null">
            <return-property name="CustomerID" column="CustomerID"></return-property>
            <return-property name="CompanyName" column="CompanyName"></return-property>
        </return>
        exec dbo.pr_GETCustomers @CustomerID=?
    </sql-query>
</hibernate-mapping>