The variable SI of type Microsoft.Xrm.Sdk.Entity is refenced on this scope, but it is not defined

Question

I have beaten my head on the wall trying to find out what is causing this error.

When I run my project it throws me the following error when I query against Dynamics CRM database using Linq Query.

The variable SI of type Microsoft.Xrm.Sdk.Entity is refenced on this scope, but it is not defined"

Important point: I have written a coment above the line that's causing the error

any help will be appreciated!

List<InnerAttributes> myQuery = (from PA in orgContext.CreateQuery("pluginassembly")
    join PT in orgContext.CreateQuery("plugintype")
    on (Guid)PA["pluginassemblyid"] equals (Guid)PT["pluginassemblyid"]
    select new InnerAttributes
    {
        assembly = PA.Contains("name") ? PA["name"].ToString() : string.Empty,

        left1 = (from S in orgContext.CreateQuery("sdkmessageprocessingstep")
            where (Guid)S["plugintypeid"] == (Guid)PT["plugintypeid"]
            select new Left1
            {
                message = S.Contains("sdkmessageid") ? S["sdkmessageid"].ToString() : string.Empty,

                left2 = (from SI in orgContext.CreateQuery("sdkmessageprocessingstepimage")
                    //Here is the error, if I take that where clause off it runs well, however it doesn't give me expected return
                    where (Guid)S["sdkmessageprocessingstepid"] == (Guid)SI["sdkmessageprocessingstepid"]
                    select new Left2
                    {
                        imageAttributes = SI.Contains("attributes") ? SI["attributes"].ToString() : string.Empty,
                    }
                ).FirstOrDefault()

            }).FirstOrDefault()

    }
).ToList();

Answer 1

This answer just expands on the comments by Nicknow and myself, so that the question can be marked as answered.

The Dynamics CRM Linq Provider requires the range variable to be the left hand term in the where clause.

Your where clause should be:

where (Guid)SI["sdkmessageprocessingstepid"] == (Guid)S["sdkmessageprocessingstepid"]

instead of:

where (Guid)S["sdkmessageprocessingstepid"] == (Guid)SI["sdkmessageprocessingstepid"]