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How to generate nHibernate raw sql for Insert/Update without execution?

Is it possible to generate a raw SQL statement for insert/update operations using nHibernate without actually executing them? Assuming of course that everything (mappings, connectionStrings, etc.) is properly configured?
The closest thing I've found is to call:
Session.SessionFactory.GetClassMetadata(typeof(Client))
Which returns an object of type SingleTableEntityPersister containing SQLIdentityInsertString, that looks like this:
INSERT INTO Client (FirstName, LastName) values (?, ?)
But it would still require me to bind all of the properties manually, and on top of that SQLIdentityInsertString is a protected property. Are there any proper ways of doing that?

Okay, the closest thing I've found is to construct your own sql query with a string builder. First you need to extract your class metadata:
var metaData = Session.SessionFactory.GetClassMetadata(typeof(Client)) as SingleTableEntityPersister;
Then you can retrieve other information, such as:
var propertyNames = metaData.PropertyNames;
var tableName = metaData.TableName;
var firstPropertyValue = metaData.GetPropertyValue(client, propertyNames[0], EntityMode.Poco);
Once you have that information you can construct your own query manually. Not exactly the solution I wanted, but it's as close as it gets, I think.
However, one thing to note is that Session.CreateSQLQuery(string) method is currently bugged, and as a result SetParameter method doesn't work with more than 10 named parameters. There already seems to be a bug report created for this on NHbiernate's Jira.

Union IQueryable and List

This is my code:
var query = context.SomeEntities.Select(e => new SomeDto
{
Name = e.Title,
})
The variable query is IQueryable.
var list = new List<SomeDto>
{
new SomeDto
{
Name = "SomeName1"
},
new SomeDto
{
Name = "SomeName2"
}
};
Now I need union these collections,I write
query = query.Union(list)
But in this place I get exception
Unable to create a constant value of type 'SomeDto'. Only primitive types or enumeration types are supported in this context
I know that I can do ToList() for first collection,but I need union collections without call to database.How can I do this?

As user3825493 pointed, there are answers regarding similar issues. The first link pretty much explains the whole thing.
Your problem is that due to the fact that Union is mapped to SQL UNION, arguments of the operation are to be converted to data types acceptable by Entity Framework. However, the only types acceptable by it for items inside IEnumerable input parameters are, as specified in the error you get, primitive types and enum's.
You should either:
var unionOfQueryWithList = query.AsEnumerable().Union(list)
or, if you like to use the SQL facilities, write a stored procedure which performs the union as part of its logic and find the way to pass your data into SQL, such as this.
The former loads all the results of the query into a memory before performing the union. It is convenient for the cases when you have all the pre-filtered data returned from EF and only want to use the output for later processing in your code.
The later takes you out of the EF zone and required for the cases when you have operations which will benefit from running on SQL engine, such as filtering or joining DB data based on a complex data you have access to in your code.

either you convert the query to IEnumerable or you can try this :
list.Union(query); // use Union() of list not query :)
it will work and you still don't need to get data from DB you can reverse the order if you want :)

Dapper with MS Access Update and Insert issue

I am using Dapper to Update and Insert Access DB. Code is working not throwing exception but its not updating the value in DB. Below is my code
sql.Append("UPDATE drugs_repository SET drug_name = #DrugName ");
sql.Append(" WHERE id = #DrugId");
var parameters = new
{
DrugName = objDrug.DrugName,
DrugId = objDrug.DrugId
};
var t = connection.Query<string>(sql.ToString(), parameters);
Can someone please let me know what exactly I am missing in the above code?
When I hardcode the value than its updating in the DB. So probably its related to parameter.

If you are nervous about possible side-effects from removing the .OrderBy() in the Dapper code then a workaround would be to name your parameters in such a way that they will sort in the same order that they appear in the SQL command. For example, I suspect that the unmodified Dapper code would probably work okay if the parameters were named #1DrugName and #2DrugId.

Linq To SQL: Sort Query by Arbitrary Property(Column) Name

I have a larger/more complex problem, but for simplicity sake, let us consider the following:
Let us say that I have table in the SQL DataBase called Product, having two columns, ID (int, primary key) and Name (varchar/string). I also have a simple LINQ DataContext.
I have a query constructed and handed to “my” function. Let us say it is something like: (though it may be a bit more complex)
IQueryable<Product> query = from p in db.Products select p;
Once my method gets this query, passed in as a parameter, it has to change the sort order e.g.
IQueryable<Product> sortedQuery = query.OrderBy(x => x.Name);
I would like to make this more generic i.e. to specify the field to sort on. Normally, I can do a switch statement that takes a string. However I would like to know if there is a way to pass the parameter directly. I intend to extend this to other Database tables, so these switch statements would get tedious.
I was trying something like:
IQueryable<Product> sortedQuery = query.OrderBy(x => (typeof(Product)).GetProperty(“Name”));
But this does not work. I also want to ensure that the LINQ to SQL is maintained i.e. the sort to be done on the SQL Server. Hence if I debug, I should get a SQL query from this LINQ query.
Thank you in advance for your help.

You could use Dynamic Linq for this purpose.
See here Dynamic LINQ (Part 1: Using the LINQ Dynamic Query Library)
Then you can make calls like this:
var query = DBContext.Users.Where( "Age > 3" ).OrderBy( "Name asc" );

Try this out instead:
query.OrderBy(x => x.GetType().GetProperty(“Name”).GetValue(x, null));
You can't just grab the property. You need to grab the value off of that property, hence the call to GetValue.

It is not as easy as it seems. The LINQ to SQL engine parses the expression you pass to the OrderBy method in order to obtain the name of the property you are referencing, then uses this information to compose a plain SQL order by clause.
I guess that maybe it can be done by using reflection, anyway. Maybe you can get something useful from the accepted answer of this SO question.

Calling a UDF with Entity SQL but without a FROM clause?

Am trying to call a UDF which just takes a parameter and returns a scalar. The examples I've seen all use a From clause: http://blogs.microsoft.co.il/blogs/gilf/archive/2009/10/20/calling-user-defined-functions-udfs-in-entity-framework.aspx
But I only want to call the UDF, I don't want to "join" it with any entities using a from clause:
string fieldTag = "TagNameHere";
var sql = "SELECT XyzModel.Store.FieldNameToFormIdMap(#fieldTag)";
System.Data.Objects.ObjectQuery<int> query =
new System.Data.Objects.ObjectQuery<int>(sql, xyzEntitiesContext);
query.Parameters.Add(new System.Data.Objects.ObjectParameter("fieldTag", fieldTag));
I get the error: "The query syntax is not valid."
This is using .NET 3.5
I could use old style ADO.NET but I'd rather not have to manage another set of connection strings aside from those used for the entity framework.

Just remove SELECT from your query, like this:
var sql = "XyzModel.Store.FieldNameToFormIdMap(#fieldTag)";