Skip to main content

SQL PARENT CHILD TREE STRUCTURE

-- DECLARE
DECLARE @Company AS TABLE(EmpID INT, ParentID INT, PersonName VARCHAR(100));

-- Insert Temp Records
INSERT INTO @Company(EmpID, ParentID, PersonName)
VALUES(1 , NULL , 'Maulik Dhorajia')
    , (2 , NULL , 'Bhavesh Gohel')
    , (3 , NULL , 'Dinesh Padhiyar')
    , (4 , 2 , 'Vijay Kumar')
    , (5 , 1 , 'Jitendra Makwana')
    , (6 , 4 , 'Jayesh Dhobi')
    , (7 , 1 , 'Shivpalsinh Jhala')
    , (8 , 5 , 'Amit Patel')
    , (9 , 3 , 'Abidali Suthar')

-- Default data

SELECT * FROM @Company;


-- Incorrect result which we usually find on Internet
;WITH CTECompany
AS
(
    SELECT EmpID, ParentID, PersonName , 0 AS HLevel
    FROM @Company
    WHERE ParentID IS NULL
   
    UNION ALL
   
    SELECT C.EmpID, C.ParentID, C.PersonName , (CTE.HLevel + 1) AS HLevel
    FROM @Company C
    INNER JOIN CTECompany CTE ON CTE.EmpID = C.ParentID
    WHERE C.ParentID IS NOT NULL
)

-- Misleading SQL
SELECT * FROM
(
    SELECT
        EmpID
        , ParentID
        , HLevel
        , (REPLICATE( '----' , HLevel ) + PersonName) AS Person
    FROM CTECompany
) AS P
ORDER BY HLevel;


-- Working Example
;WITH CTECompany
AS
(
    SELECT
        EmpID,
        ParentID,
        PersonName ,
        0 AS HLevel,
        CAST(RIGHT(REPLICATE('_',5) +  CONVERT(VARCHAR(20),EmpID),20) AS VARCHAR(MAX)) AS OrderByField
    FROM @Company
    WHERE ParentID IS NULL
   
    UNION ALL
   
    SELECT
        C.EmpID,
        C.ParentID,
        C.PersonName ,
        (CTE.HLevel + 1) AS HLevel,
        CTE.OrderByField + CAST(RIGHT(REPLICATE('_',5) +  CONVERT(VARCHAR(20),C.EmpID),20) AS VARCHAR(MAX)) AS OrderByField
    FROM @Company C
    INNER JOIN CTECompany CTE ON CTE.EmpID = C.ParentID
    WHERE C.ParentID IS NOT NULL
)

-- Working Example
SELECT
    EmpID
    , ParentID
    , HLevel
    , PersonName
    , (REPLICATE( '----' , HLevel ) + PersonName) AS Person
FROM CTECompany
ORDER BY OrderByField,PersonName;

Comments

Post a Comment

Popular posts from this blog

Dynamic Generation of Word Document Report in ASP.NET with HTML

Overview Ever needed to generate Word documents from your ASP.NET applications? There are a couple of components which will help to generate Word documents, but using these components may have some overhead such as Component Registration, setting permissions, licenses, etc., Sometimes, it may even become difficult to understand their features and use them. Generating word document in ASP.NET with HTML is incredibly easy. The following sample demonstrates how to place Heading and Table dynamically in the word document in ASP.NET web applications using HTML. Requirements Microsoft Visual Web Developer 2005 Express Edition Create the Web Application project Add the new Web Site Application project (with name as Generate Word Document) and place the button (with name as btnGenerateDocument) in the Default.aspx web form as shown below. Double click the highlighted code behind file from the Solution Explorer and add the following namespaces. Listing 1 using  System...
Post a Comment
Read more

GRIDVIEW ZOOM IMAGE

When you have images in your  GridView , you would most likely show them as thumbnails so as to not distort the whole layout. However user would want to look at the full image by clicking on the image or just hovering his mouse over it. In today’s applications, this is a basic requirement and there are just so many third party controls or plugins which would support this functionality. I am going do this conventional way using  javascript  way in this article.  On top of it, I am also going to explain how to get images from database using  HttpHandlers . Example: I am using  Adventure Works  as datasource. We fetch handful of products and bind them to the grid. When page is initially loaded, we retrieve products from Production . Product  table and bind them to the grid. We display some product attributes such as Product ID, Product Number, Product Name, List Price and product’s thumbnail. When user hover his mouse on the page, we fetch the f...
Post a Comment
Read more

GRIDVIEW GROUPING

When displaying data, we sometimes would like to group data for better user experience or when displaying long list of hierarchal data, we would want to display them in a tree view kind of structure. There is more than way of doing this, but I am going to explain achieving this functionality using  AJAX Collapsible Panel Extender Control . Overview: I am going to use  Adventure Works  as datasource. Every product in  Production.Product  table belongs to a product sub category. We fetch handful of products and the sub categories they belong to from the database. Our objective is to list all the available sub categories and allow user to  expand/collapse  to look/hide the list of products belonging to each subcategory. Database Connection Added following entry under  connectionStrings  element in  web.config . < add   name = "Sql"   connectionString="Data Source=(local); Initial  Catalog = AdventureWorks ...
Post a Comment
Read more