Concatenate colums's data in sql query

Introduction

May time we need column?s data into a single row from a database table. This is easy to do if we are doing this at application level. However this could also be done in a sql query. Let?s take an example. 

Suppose we have a table for "Fruits": 

SELECT * FROM Fruits

FruitId      FruitName
-----------------------
1001         Apple
1002         Orange
1003         Mango
1004         Banana
1005         Grape

Now my need is to show all fruits in a single row separated by comma (,). One commonly used approach is to fetch all rows and concatenate data into out application 

while (dr.Read())
{
  fruitNames += dr["FruitName"] + ",";
}

We can do the same thing in a Sql Server Query also 

DECLARE @fruitNames VARCHAR(8000) 
SELECT @fruitNames = COALESCE(@fruitNames + ', ', '') + FruitName FROM Fruits
SELECT FruitNames = @fruitNames

FruitNames
----------
Apple, Orange, Mango, Banana, Grape