linq to sql Distinct and orderby

var result = table1.Join(table2, o => o.ProgramID, t => t.ProgramID, (o, t) => new { o.ProgramID, t.Program })
         .OrderBy(t => t.Program)
         .Distinct();

the above linq stateme开发者_运维百科nt actually returns the correct result, but he sql generated (below) is not as simple as it could be

SELECT [t2].[ProgramID], [t2].[Program]
FROM (
    SELECT DISTINCT [t0].[ProgramID], [t1].[Program]
    FROM [table1] AS [t0]
    INNER JOIN [table2] AS [t1] ON [t0].[ProgramID] = [t1].[ProgramID]
    ) AS [t2]
ORDER BY [t2].[Program]

I would have thought the sql below is far cleaner but I'm not sure of the linq statement to achieve it.

select distinct 
    o.ProgramID, 
    t.Program 
from 
    table1 0 
    inner join table2 t on t.ProgramID = o.ProgramID 
order by t.Program

Thanks in advance

I don't know if it will help, but you can try something like this;

var result = (from o in table1
              join t in table2 on o.ProgramID equals t.ProgramID
              orderby t.Program
              select new { o.ProgramID, t.Program }).Distinct();

I tried this and that works:

var result = (from o in table1
              join t in table2 on o.ProgramID equals t.ProgramID
              select new { o.ProgramID, t.Program })
              .Distinct().OrderBy(t => t.Program)
                         .ThenBy(t => t.ProgramName)
                         .ThenBy(t => t.Description); 

First you do Distinct and then OrderBy, then OrderBy works.

Profile the two queries, comparing stats-IO and the actual execution plan. It is entirely possible that it makes zero difference to the SQL server.

If you really want known TSQL, use ExecuteQuery-of-T and pass in the TSQL yourself. Maybe include some lock hints too (most commonly: NOLOCK)