Question

I have an ASP.NET MVC Web Application that interacts with a SQL Server 2008 database via Entity Framework 4.0.

On a particular page, i call a stored procedure in order to pull back some results based on selections on the UI.

Now, the UI has around 20 different input selections, ranging from a textbox, dropdown list, checkboxes, etc.

Each of those inputs are “grouped” into logical sections.

Example:

• Search box : “Foo”
• Checkbox A1: ticked, Checkbox A2: unticked
• Dropdown A: option 3 selected
• Checkbox B1: ticked, Checkbox B2: ticked, Checkbox B3: unticked

So i need to call the SPROC like this:

exec SearchPage_FindResults @SearchQuery = 'Foo', @IncludeA1 = 1, @IncludeA2 = 0, @DropDownSelection = 3, @IncludeB1 = 1, @IncludeB2 = 1, @IncludeB3 = 0

The UI is not too important to this question – just wanted to give some perspective.

Essentially, i’m pulling back results for a search query, filtering these results based on a bunch of (optional) selections a user can filter on.

Now, My questions/queries:

• What’s the best way to pass these parameters to the stored procedure?
• Are there any tricks/new ways (e.g SQL Server 2008) to do this? Special “table” parameters/arrays – can we pass through User-Defined-Types? Keep in mind im using Entity Framework 4.0 – but could always use classic ADO.NET for this if required.
• What about XML? What are the serialization/de-serialization costs here? Is it worth it?
• How about a parameter for each logical section? Comma-seperated perhaps? Just thinking out loud.

This page is particulary important from a user point of view, and needs to perform really well. The stored procedure is already heavy in logic, so i want to minimize the performance implications – so keep that in mind.

With that said – what is the best approach here?

Answer 1

By a quick Googling, it looks like Entity Framework doesn’t support them, but you can use Table Valued Parameters in ADO.

You manage that by defining a table type in your server:

CREATE TYPE yourTypeName AS TABLE (
    columnName <column type>
    -- more columns if you wish, too
)

and then use it by making a SqlCommand, and doing this:

SqlParameter param = command.CreateParameter();
param.ParameterName = "@something"
param.SqlDbType = SqlDbType.Structured
param.Value = // a DataTable which matches your table type, I can stick in code I use if you like
param.TypeName = "table type name";

And your procedures will look like this:

CREATE PROCEDURE procName
@something yourTypeName READONLY
AS
BEGIN
...

Your SQL queries will then use that parameter as if it were a table, though it’s read-only.

Performance-wise, I’m not a DBA, and I’m not sure how fast XML is – I gather it’s pretty quick. TVPs though are rather blazingly fast, and even the relatively-simple DataTable method I’ve used runs great. There’s more about TVPs here, and quite a few blog posts out there about SQL and TVPs in general.