Question

I’m trying to rewrite a SQL query in LINQ to Entities. I’m using LINQPad with a typed datacontext from my own assembly to test things out.

The SQL query I’m trying to rewrite:

SELECT DISTINCT variantID AS setID, option_value AS name, option_value_description AS description, sort_order as sortOrder
FROM all_products_option_names AS lst
WHERE lst.optionID=14 AND lst.productID IN (SELECT productID FROM all_products_option_names
                                            WHERE optionID=7 AND option_value IN (SELECT name FROM brands
                                                                                  WHERE brandID=1))
ORDER BY sortOrder;

The LINQ to Entities query I’ve come up with so far (which doesn’t work due to a timeout error):

from a in all_products_option_names
where a.optionID == 14 && all_products_option_names.Any(x => x.productID == a.productID && x.optionID == 7 && brands.Any(y => y.name == x.option_value && y.brandID == 1))
select new
{
    id = a.variantID,
    name = a.option_value,
    description = a.option_value_description,
    sortOrder = a.sort_order,
}

This is the error I get when I run the above query: An error occurred while executing the command definition. See the inner exception for details.

And the inner exception is: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.

Edit:

I use MySQL and probably that’s why LINQPad doesn’t show me the generated SQL.

The SQL version doesn’t time out.

Edit 2:

I solved the problem by completely changing the query, so this question is irrelevant now.

I marked Steven’s response as the correct one, because he was closest to what i was trying to achieve and his response gave me the idea which led me to the solution.

Answer 1

Try this:

var brandNames =
    from brand in db.Brands
    where brand.ID == 1
    select name;

var brandProductNames =
    from p in db.all_products_option_names
    where p.optionID == 7
    where brandNames.Contains(p.option_value)
    select p.productId;

var results =
    from p in db.all_products_option_names
    where p.optionID == 14
    where brandProductNames.Contains(p.productId)
    select new
    {
        setID = p.variantID, 
        name = p.option_value, 
        description = p.option_value_description, 
        sortOrder = p.sort_order
    };