Linq selecting range of records

Question

    var q = (from Comments in db.tblBlogComments where Comments.blogID == this.ID orderby Comments.date descending select new {
        Comments.userID, Comments.com         


        

Answer 1

int start = 10;
int end = 20;
var q = (from Comments in db.tblBlogComments 
            where Comments.blogID == this.ID 
            orderby Comments.date descending 
            select new {
                          Comments.userID, 
                          Comments.comment, 
                          Comments.date
                       }).Skip(start).Take(end - start);

I'm not sure if Skip translates to SQL executed in the database, so this might be not so efficient.

Answer 2

How about:

var q = (
from Comments in db.tblBlogComments 
where Comments.blogID == this.ID 
orderby Comments.date descending 
select new { Comments.userID, Comments.comment, Comments.date }).Skip(10).Take(10);

Answer 3

You can use the .Skip() and .Take() methods on your result set. Example:

var q = (from Comments in db.tblBlogComments where Comments.blogID == this.ID orderby Comments.date descending select new {
    Comments.userID, Comments.comment, Comments.date
});

And then use:

int pageSize = 10;
int page = 3;
var currentPage = q.Skip((currentPage - 1) * pageSize).Take(pageSize);

And then

foreach(var item in currentPage)
{
    ...
}

Since Linq uses deferred execution, the actual query will be created and executed during the foreach loop. So the SQL query will only return the records for the current page.

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