Paging in Entity Framework

Question

In Entity Framework, using LINQ to Entities, database paging is usually done in following manner:

int totalRecords = EntityContext.Context.UserSet.Count;
var         


        

Answer 1

Suppose you want to get the details of Page 2 with a pagesize=4

int page =2;
int pagesize=4;

var pagedDetails= Categories.Skip(pagesize*(page-1)).Take(pagesize)
.Join(Categories.Select(item=>new {item.CategoryID,Total = Categories.Count()}),x=>x.CategoryID,y=>y.CategoryID,(x,y)=>new {Category = x,TotalRows=y.Total});

The Output will have all details of Category and TotalRows.

One DB call.

Generated SQL

-- Region Parameters
DECLARE @p0 Int = 2
DECLARE @p1 Int = 4
-- EndRegion
SELECT [t2].[CategoryID], [t2].[CategoryName], [t2].[Description], [t2].[Picture], [t5].[value] AS [TotalRows]
FROM (
    SELECT [t1].[CategoryID], [t1].[CategoryName], [t1].[Description], [t1].[Picture], [t1].[ROW_NUMBER]
    FROM (
        SELECT ROW_NUMBER() OVER (ORDER BY [t0].[CategoryID], [t0].[CategoryName]) AS [ROW_NUMBER], [t0].[CategoryID], [t0].[CategoryName], [t0].[Description], [t0].[Picture]
        FROM [Categories] AS [t0]
        ) AS [t1]
    WHERE [t1].[ROW_NUMBER] BETWEEN @p0 + 1 AND @p0 + @p1
    ) AS [t2]
INNER JOIN (
    SELECT [t3].[CategoryID], (
        SELECT COUNT(*)
        FROM [Categories] AS [t4]
        ) AS [value]
    FROM [Categories] AS [t3]
    ) AS [t5] ON [t2].[CategoryID] = [t5].[CategoryID]
ORDER BY [t2].[ROW_NUMBER]