Using LINQ-To-Entities to Generate Information

Posted by parminder on Stack Overflow See other posts from Stack Overflow or by parminder
Published on 2010-05-20T19:39:09Z Indexed on 2010/05/21 3:50 UTC
Read the original article Hit count: 315

Filed under:

linq-to-entities

|

asp.net-mvc

|

LINQ

|

.NET

|

c#

I am working on a website where a user can add tags to their posted books, much like is currently done for questions on Stack Overflow.

Classes:

Books
{
bookId,
Title
}

Tags
{
Id
Tag
}

BooksTags
 {
 Id
 BookId
 TagId
 }

Here are few sample records.

Books
BookId Title
113421  A
113422  B

Tags
Id Tag
1  ASP 
2  C#
3  CSS
4  VB
5  VB.NET
6  PHP
7  java
8  pascal

 BooksTags   
 Id  BookId  TagId
 1  113421    1
 2  113421    2
 3  113421    3
 4  113421    4
 5  113422    1
 6  113422    4
 7  113422    8

Questions

I need to write something in LINQ to entity queries which gives me data according to the tags:

Query: bookIds where tagid = 1
Returns: bookid: 113421, 113422

Query 2: tags 1 and 2
Returns: 113421
I need tags and their count to to show in related tags, so in first case my related tags class should have following result.

RelatedTags Tag Count 2 1 3 1 4 2 8 1

Second Case:

RelatedTags
Tag Count
3   1
4   1

How do I do this in LINQ?

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