Move Node to other place with HierarchyId Data Type - SQL Server 2008 by serverku

After writing some of the posts related HierachyId data type, Finally moving in last topics of HierachyId functions, we will see here the movement of the hierarchy nodes. Let's start from the script to create data for the demo.

-- Create database and table
CREATE DATABASE HierarchyDB

GO

USE HierarchyDB

GO

IF ( Object_id('HierarchyTab') > 0 )
DROP TABLE HierarchyTab

GO

CREATE TABLE HierarchyTab
(
NodeId     INT IDENTITY(1, 1)
,NodeDepth VARCHAR(100) NOT NULL
,NodePath  HIERARCHYID NOT NULL
,NodeDesc  VARCHAR(100)
)

GO 

-- Creating constraint on hierarchy data type.
ALTER TABLE HierarchyTab ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)

GO 
-- Inserting data in above creatd table.
INSERT INTO HierarchyTab(NodeDepth,NodePath,NodeDesc)
VALUES 
('1',HIERARCHYID::Parse('/'),'Node-1'),
('1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
('1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
('1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
('1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
('1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
('1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
('1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
('1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9'),
('1.2.2.1.2',HIERARCHYID::Parse('/2/2/1/2/'),'Node-10'),
('1.3',HIERARCHYID::Parse('/3/'),'Node-11'),
('1.3.1',HIERARCHYID::Parse('/3/1/'),'Node-12'),
('1.3.2',HIERARCHYID::Parse('/3/2/'),'Node-13'),
('1.4',HIERARCHYID::Parse('/4/'),'Node-14')

GO

The logical image of hierarchy data are as following,

(Click on image to enlarge)
Now we will move hierarchy nodes and it's down-line from one place to another place.

But how to move?


GetReparentedValue(OldNode, NewNode) : It will move all nodes, including itself and down-line as well to another place. Let's see  what should be new place of the hierarchy id "1" and it's down-line nodes after moving to another place.

-- GetReparentedValue()
SELECT 
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeCurrentPath,
NodePath.GetReparentedValue(HIERARCHYID::Parse('/1/'), HIERARCHYID::Parse('/4/1/')).ToString()
 AS NewNodePath,
-- Above line will give new node path of id 1 and it's downline where it will be placed.
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab
WHERE NodePath.IsDescendantOf(HIERARCHYID::Parse('/1/')) = 1

GO

(Click on image to enlarge)


Now run the below query and move the id 1 and down-line of hierarchy id and then see a logical image from data

UPDATE HierarchyTab
SET NodePath  = NodePath.GetReparentedValue(HIERARCHYID::Parse('/1/'), HIERARCHYID::Parse('/4/1/')),
NodeDepth = '4.' + NodeDepth
WHERE NodePath.IsDescendantOf(HIERARCHYID::Parse('/1/')) = 1

GO

(Click on image to enlarge)

Hope you understood well and get used this feature for the hierarchical data. Please comments how you are using HierarchyId Data Type and their functions.

Is Child Node? - With HierarchyId Data Type in SQL Server 2008 by serverku

Various method I have introduced in my earlier posts, like How to get levels of hierarchy nodes, get up-line and down-line of nodes, get string paths of nodes and get next available nodes.

I hope you have read all of them and you liked too. In this post I am presenting how can we know the node is child of particular node or not? Before going ahead to run the script and see the output of hierarchy structure.

-- Create database and table
CREATE DATABASE HierarchyDB

GO

USE HierarchyDB

GO

IF ( Object_id('HierarchyTab') > 0 )
DROP TABLE HierarchyTab

GO

CREATE TABLE HierarchyTab
(
NodeId     INT IDENTITY(1, 1)
,NodeDepth VARCHAR(100) NOT NULL
,NodePath  HIERARCHYID NOT NULL
,NodeDesc  VARCHAR(100)
)

GO 

-- Creating constraint on hierarchy data type.
ALTER TABLE HierarchyTab ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)

GO 
-- Inserting data in above creatd table.
INSERT INTO HierarchyTab(NodeDepth,NodePath,NodeDesc)
VALUES 
('1',HIERARCHYID::Parse('/'),'Node-1'),
('1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
('1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
('1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
('1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
('1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
('1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
('1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
('1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9'),
('1.2.2.1.2',HIERARCHYID::Parse('/2/2/1/2/'),'Node-10'),
('1.3',HIERARCHYID::Parse('/3/'),'Node-11'),
('1.3.1',HIERARCHYID::Parse('/3/1/'),'Node-12'),
('1.3.2',HIERARCHYID::Parse('/3/2/'),'Node-13'),
('1.4',HIERARCHYID::Parse('/4/'),'Node-14')

GO

Here is the logical image of the above data are as follows,

(Click on image to enlarge)

So our topic here, Is the node Child ?

IsDescendantOf() : This functions will return 1 if the node is child of given node, return 0 if the node is not child.

Let's run the script with example as who are child of hierarchy node "1".

SELECT 
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeStringPath,
NodePath.GetAncestor(1).ToString() AS ParentNode,
NodePath.IsDescendantOf(HIERARCHYID::Parse('/1/')) IsParent,
-- Above line will return 1 or 0
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab

GO

You can see the above image and check parent node for appropriate child nodes. Hope you like this. Stay tuned for more.

Next Available Node with HierarchyId Data Type - SQL Server 2008 by serverku

I have posted for the some of the functions with examples and demonstrate them in earlier posts. I have written articles of HierarchyId data type overview, some basic functions, even demonstrate for the up-line & down-line of hierarchy nodes which you can read from below links.

Here I will present how can we get the next available node to be planed with HierarchyID data type function. Let's first create hierarchy data structure with the script.

-- Create a database and table
CREATE DATABASE HierarchyDB

GO

USE HierarchyDB

GO

IF ( Object_id('HierarchyTab') > 0 )
DROP TABLE HierarchyTab

GO

CREATE TABLE HierarchyTab
(
NodeId     INT IDENTITY(1, 1)
,NodeDepth VARCHAR(100) NOT NULL
,NodePath  HIERARCHYID NOT NULL
,NodeDesc  VARCHAR(100)
)

GO 

-- Creating constraint on hierarchy data type.
ALTER TABLE HierarchyTab ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)

GO 
-- Inserting data in above creatd table.
INSERT INTO HierarchyTab(NodeDepth,NodePath,NodeDesc)
VALUES 
('1',HIERARCHYID::Parse('/'),'Node-1'),
('1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
('1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
('1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
('1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
('1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
('1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
('1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
('1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9'),
('1.2.2.1.2',HIERARCHYID::Parse('/2/2/1/2/'),'Node-10'),
('1.3',HIERARCHYID::Parse('/3/'),'Node-11'),
('1.3.1',HIERARCHYID::Parse('/3/1/'),'Node-12'),
('1.3.2',HIERARCHYID::Parse('/3/2/'),'Node-13'),
('1.4',HIERARCHYID::Parse('/4/'),'Node-14')

GO

Hierarchy data structure as imaged as below.

(Click on image to enlarge)

How to we find it?

GetDescendant() : This function will give next available node where we can place new node.

1. GetDescendant(NULL,NULL) : will return default next left node.
2. GetDescendant(LeftNode,NULL) : will return right node next to left node.
3. GetDescendant(NULL,RighNode) : will return left node previous to left node.

Run the following script and see the output.

-- GetDescendant()
SELECT 
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeStringPath,
NodePath.GetDescendant(NULL,NULL).ToString() AS NextDefaultNode,
-- Above line will get default node.
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab

GO

Looking for one hierarchy node id 13,

SELECT 
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeStringPath,
NodePath.GetDescendant(NULL,NULL).ToString() AS NextDefaultNode,
NodePath.GetDescendant(HIERARCHYID::Parse('/3/2/1/'),NULL).ToString() AS NextRightNode,
NodePath.GetDescendant(NULL,HIERARCHYID::Parse('/3/2/2/')).ToString() AS NextLeftNode,
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab
WHERE NodeId = 13

GO

(Click on image to enlarge)

This is what I want to share here and hope you like it.

Up-Line and Down-Line with HierarchyId Data type - SQL Server 2008 by serverku

I have already given HierarchyId datatype overview in my earlier post. Also explained some of HierarchyId functions in post with details as well. Please go through to the overview and some function details which I explained in my previous posts. In this article I am going to demonstrate following items.

1. How to get the up-line nodes?
2. How to get down-line nodes?

Hierarchies functions will give you the answer to all above questions. Let's demonstrate the answers with examples. Before going ahead, I would like to create a hierarchy data structure by following a script.

-- Create database and table
CREATE DATABASE HierarchyDB

GO

USE HierarchyDB

GO

IF ( Object_id('HierarchyTab') > 0 )
DROP TABLE HierarchyTab

GO

CREATE TABLE HierarchyTab
(
NodeId     INT IDENTITY(1, 1)
,NodeDepth VARCHAR(100) NOT NULL
,NodePath  HIERARCHYID NOT NULL
,NodeDesc  VARCHAR(100)
)

GO 

-- Creating constraint on hierarchy data type.
ALTER TABLE HierarchyTab ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)

GO 
-- Inserting data in above creatd table.
INSERT INTO HierarchyTab(NodeDepth,NodePath,NodeDesc)
VALUES 
('1',HIERARCHYID::Parse('/'),'Node-1'),
('1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
('1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
('1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
('1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
('1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
('1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
('1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
('1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9'),
('1.2.2.1.2',HIERARCHYID::Parse('/2/2/1/2/'),'Node-10'),
('1.3',HIERARCHYID::Parse('/3/'),'Node-11'),
('1.3.1',HIERARCHYID::Parse('/3/1/'),'Node-12'),
('1.3.2',HIERARCHYID::Parse('/3/2/'),'Node-13'),
('1.4',HIERARCHYID::Parse('/4/'),'Node-14')

GO

The structure of HierarchyId data looks as follows,

(Clink on image to enlarge)

Now we have time to demonstrate the answers one by one here.

1. How to get the up-line nodes?

GetAncestor(n) : This function will help us to get up-line of the particular hierarchy node. Looking at the script, which will find first up-line node of all hierarchy nodes.

-- GetAncestor(n)
SELECT 
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeStringPath,
NodePath.GetAncestor(1).ToString() AS ParentNode,
-- Here 1 is used to get 1st u-line node
-- You can use n to get nth up-line node
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab

GO

Please change value to 2 as GetAncestor(n) in place of 1 in script and get the output, You will get more idea.

2. How to get down-line nodes?

IsDescendantOf() : This function will give us the down-line noes of a particular node. Let us run the script and clear our answer. We are viewing a downline node of hierarchy node 1 by script.

-- IsDescendantOf()
SELECT  
NodePath.GetLevel() AS NodeLevel,
NodePath.ToString() AS NodeStringPath,
NodeId,
NodeDepth,
NodePath,
NodeDesc
FROM HierarchyTab
WHERE NodePath.IsDescendantOf(HIERARCHYID::Parse('/1/')) = 1
-- Here we have filtered condition to get down-line of node 1.
GO

I hope you are very clear now after demonstrate to how get up-line and down-line of hierarchy node.

Get Downline and Upline of hierarchical data and Performance review - CTE vs HierarchyId in SQL Server 2008 by serverku

I have already posted for the HierarchyId and CTE (Common Table Expression), also given the comparison review of them for the level and hierarchical order data. I am not saying that HierarchyId is better than CTE or CTE is better then HierarchyId. But it all depends on. You need to practically use them and review the performance of hierarchies and CTE. I am going to show one more demo to find the members with downline and upline.

-- creating database and objects
CREATE DATABASE HierarchyDB
GO

USE HierarchyDB
GO

IF ( Object_id('HierarchyTab') > 0 )
  DROP TABLE HierarchyTab
GO

CREATE TABLE HierarchyTab
  (
     NodeId     INT NOT NULL
     ,NodeParent int
     ,NodeDepth VARCHAR(100) NOT NULL
     ,NodePath  HIERARCHYID NULL
     ,NodeLevel as (NodePath.[GetLevel]())
     ,NodeStringPath as  (NodePath.ToString())
     ,NodeDesc  VARCHAR(100)
  )
GO 

ALTER TABLE HierarchyTab ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)
GO 

INSERT INTO HierarchyTab(NodeId,NodeParent,NodeDepth,NodePath,NodeDesc)
VALUES 
(1,NULL,'1',HIERARCHYID::Parse('/'),'Node-1'),
(2,1,'1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
(3,2,'1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
(4,2,'1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
(5,1,'1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
(6,5,'1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
(7,5,'1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
(8,7,'1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
(9,8,'1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9')
GO

SELECT 
* 
FROM HierarchyTab
GO

1. Get down line data using CTE and HierarchyId and compare the execution plan.

-- Using CTE (Not Using NodePath and NodeLevel)
;WITH cteLevels
AS
(
SELECT
    NodeId as Node
    ,NodeParent as Perent 
    ,NodeDepth as Depth
    ,0        AS [Level]
    ,NodeDesc as [Desc]
FROM   HierarchyTab 
WHERE NodeId = 1

UNION ALL

SELECT
     NodeId 
    ,NodeParent 
    ,NodeDepth
    ,[Level] + 1 AS [Level]
    ,NodeDesc 
FROM   HierarchyTab
       INNER JOIN cteLevels
         ON ( NodeParent = Node ) 
WHERE [Level] + 1 < =3
)

SELECT 
* 
FROM cteLevels 
WHERE [Level] = 3
GO


-- With HierarchyId
DECLARE @DownlineNode HierarchyId = 
(SELECT NodePath FROM HierarchyTab WHERE NodeId = 1)

SELECT 
 NodePath.ToString() AS NodeStringPath,
 NodeId,
 NodeParent,
 NodeDepth,
 NodeLevel,
 NodeDesc
FROM HierarchyTab
WHERE NodePath.IsDescendantOf(@DownlineNode) = 1
AND NodeLevel = @DownlineNode.GetLevel() + 3
GO

When you run above script you have data and execution plans as follow,

2. Get up line data using CTE and HierarchyId and compare the execution plan.

-- Using CTE (Not Using NodePath and NodeLevel)
;WITH cteLevels
AS
(
SELECT
    NodeId as Node
    ,NodeStringPath as StringPath
    ,NodeParent as Parent 
    ,NodeDepth as Depth
    ,0        AS [Level]
    ,NodeDesc as [Desc]
FROM   HierarchyTab 
WHERE NodeId = 9


UNION ALL

SELECT
    NodeId 
    ,NodeStringPath as StringPath
    ,NodeParent 
    ,NodeDepth
    ,[Level] + 1 AS [Level]
    ,NodeDesc 
FROM   HierarchyTab
       INNER JOIN cteLevels
         ON ( NodeId = Parent ) 
WHERE [Level] + 1 < =3
)

SELECT 
* 
FROM cteLevels 
WHERE [Level] = 3
GO


-- With HierarchyId
SELECT 
 NodePath.ToString() AS NodeStringPath,
 NodeId,
 NodePath.GetAncestor(3).ToString() as ParentOn4thPos,
 NodeParent,
 NodeDepth,
 NodeLevel,
 NodeDesc
FROM HierarchyTab
WHERE NodeId = 9
GO

The result set and execution plan when you run above script

Hope you like this and share your experience as comments.

Breath First and Depth First Strategy with Hierarchical Data and Performance review - HierarchyId Data Type vs CTE in SQL Server 2008 by serverku

It is very important to check the performance if we use the new features of alternative methods of SQL Server. I have written earlier posts of the HierarchyId and CTE (Common Table expression). Now in this post you can view the usage of HierarchyId and CTE, comparisons between them. Go ahead with the object creation.

1. Introduction to HierarchyId data type - Amazing feature of SQL Server 2008
2. HierarchyId DataType in SQL Server 2008 - Get Level and String Path

-- Creating databse and table
CREATE DATABASE HierarchyDB
GO

USE HierarchyDB
GO

IF ( Object_id('HierarchyTab') > 0 )
DROP TABLE HierarchyTab
GO

CREATE TABLE HierarchyTab
(
  NodeId     INT NOT NULL
 ,NodeParent int
 ,NodeDepth VARCHAR(100) NOT NULL
 ,NodePath  HIERARCHYID NULL
 ,NodeLevel as (NodePath.[GetLevel]()) 
 ,NodeDesc  VARCHAR(100)
)
GO 

ALTER TABLE HierarchyTab 
ADD CONSTRAINT U_NodePath UNIQUE CLUSTERED (NodePath)
GO 

Inserting demo records in table created above.

INSERT INTO HierarchyTab(NodeId,NodeParent,NodeDepth,NodePath,NodeDesc)
VALUES 
(1,NULL,'1',HIERARCHYID::Parse('/'),'Node-1'),
(2,1,'1.1',HIERARCHYID::Parse('/1/'),'Node-2'),
(3,2,'1.1.1',HIERARCHYID::Parse('/1/1/'),'Node-3'),
(4,2,'1.1.2',HIERARCHYID::Parse('/1/2/'),'Node-4'),
(5,1,'1.2',HIERARCHYID::Parse('/2/'),'Node-5'),
(6,5,'1.2.1',HIERARCHYID::Parse('/2/1/'),'Node-6'),
(7,5,'1.2.2',HIERARCHYID::Parse('/2/2/'),'Node-7'),
(8,7,'1.2.2.1',HIERARCHYID::Parse('/2/2/1/'),'Node-8'),
(9,8,'1.2.2.1.1',HIERARCHYID::Parse('/2/2/1/1/'),'Node-9')
GO

Now we will check the usage  and execution plan of the HierarchyId and CTE.

1. First, we will run the scripts for the to get data level by level order. Let’s start with CTE and the query without using a hierarchy node,

-- Using CTE (Not Using NodePath and NodeLevel)
;WITH cteLevels
AS
(
SELECT
  NodeId as Node
 ,NodeParent as Perent 
 ,NodeDepth as Depth
 ,0        AS [Level]
 ,NodeDesc as [Desc]
FROM   HierarchyTab 
WHERE NodeId = 1


UNION ALL

SELECT
  NodeId 
 ,NodeParent 
 ,NodeDepth
 ,[Level] + 1 AS [Level]
 ,NodeDesc 
FROM   HierarchyTab
INNER JOIN cteLevels
ON ( NodeParent = Node ) 

)

select 
* 
from cteLevels 
Order by [Level]
GO

Now running the script to get hierarchy data level by level order using HierarchyId,

-- With HierarchyId
SELECT 
  NodePath.ToString() AS NodeStringPath,
  NodeId,
  NodeParent,
  NodeDepth,
  NodeLevel,
  NodeDesc
FROM HierarchyTab
Order by NodeLevel

GO

Before going ahead with next script, we are checking the execution plan of both above script,

2. Getting records of hierarchy in hierarchical order with CTE and HierarchyId.

-- Using CTE (Not Using NodePath and NodeLevel)
;WITH cteLevels
AS
(
SELECT
  NodeId as Node
 ,NodeParent as Perent 
 ,NodeDepth as Depth
 ,0        AS [Level]
 ,NodeDesc as [Desc]
 ,CAST(NodeId AS VARCHAR(MAX))  AS [Order]
FROM   HierarchyTab 
WHERE NodeId = 1


UNION ALL

SELECT
  NodeId 
 ,NodeParent 
 ,NodeDepth
 ,[Level] + 1 AS [Level]
 ,NodeDesc 
 ,[Order] + '.' + CAST(NodeId AS VARCHAR(MAX)) AS [Order]
FROM   HierarchyTab
INNER JOIN cteLevels
ON ( NodeParent = Node ) 

)

SELECT 
* 
FROM cteLevels 
ORDER BY [Order]

GO

View the result of hierarchical order data with running below query with HierarhyId,

-- With HierarchyId
SELECT 
 NodePath.ToString() AS NodeStringPath,
 NodeId,
 NodeParent,
 NodeDepth,
 NodeLevel,
 NodeDesc
FROM HierarchyTab
Order by NodePath

GO

Finally, we go through the performance and the execution plan review of both above scripts,

This is just the details of execution and performance review.

MERGE statement - a new tsql feature of SQL Server 2008 by serverku

It will a lengthy and complex coding if we need to perform insert, update and delete statement individually. Instead of writing separate statements for the insert, update and delete operation, we have one more option which can be very helpful in this matter.

Yes, that feature is "Merge" statement and supported in SQL server 2008 or later version. Merge is allow multiple DML operation to perform. That must be ended by semicolon. Let's see the example using Merge statement.

-- Creating Database

CREATE DATABASE MergeDatabase

GO

USE MergeDatabase

GO

-- Creating tables used for merged operation

IF ( Object_id('UsingTable') > 0 )
  DROP TABLE UsingTable

GO

CREATE TABLE UsingTable
  (
     RefId INT IDENTITY(1, 1),
     name  VARCHAR(100)
  )

GO

IF ( Object_id('TargetTable') > 0 )
  DROP TABLE TargetTable

GO

CREATE TABLE TargetTable
  (
     ChildId INT,
     val     INT
  )

GO

-- Inserting records in both tables

INSERT INTO UsingTable(name)
VALUES      ('Target-1'),
            ('Target-2'),
            ('Target-3'),
            ('Target-4'),
            ('Target-5')

GO

INSERT INTO TargetTable(ChildId,val)
VALUES      (1,1),
            (2,2),
            (3,3),
            (6,6) 

GO

Let us see how Merge statement works.

1. Merge statement with WHEN MATCHED clause and updating records,>

MERGE TargetTable 
USING UsingTable
ON (RefId = ChildId)

WHEN MATCHED THEN
UPDATE set val = val + 5 ;

2. Merge statement with WHEN MATCHED clause and deleting records,

MERGE TargetTable
USING UsingTable
ON (RefId = ChildId)

WHEN MATCHED AND ChildId = 3 THEN
DELETE ;

3. Merge statement with WHEN NOT MATCHED BY TARGET clause and inserting records,

MERGE TargetTable
USING UsingTable
ON (RefId = ChildId)

WHEN NOT MATCHED BY TARGET THEN
INSERT(childId,val)
VALUES(4,4)
;

4. Merge statement with WHEN NOT MATCHED BY SOURCE clause and deleting records,

MERGE TargetTable
USING UsingTable
ON (RefId = ChildId)

WHEN NOT MATCHED BY SOURCE
THEN DELETE;

5. All together at once,

MERGE TargetTable
USING UsingTable
ON (RefId = ChildId)


WHEN MATCHED AND ChildId = 3 THEN
DELETE 

WHEN MATCHED THEN
UPDATE set val = val + 5

WHEN NOT MATCHED BY TARGET THEN
INSERT(childId,val)
VALUES(4,4)

WHEN NOT MATCHED BY SOURCE
THEN DELETE;

Let's see the result set of TargetTable before and after the Merge statement used.

Before Merge statement ran,

After Merge statement ran,

6. Using OUTPUT with Merge statement,

MERGE TargetTable
USING UsingTable
ON (RefId = ChildId)


WHEN MATCHED AND ChildId = 3 THEN
DELETE 

WHEN MATCHED THEN
UPDATE set val = val + 5

WHEN NOT MATCHED BY TARGET THEN
INSERT(childId,val)
VALUES(4,4)

WHEN NOT MATCHED BY SOURCE
THEN DELETE

OUTPUT

$action,
INSERTED.ChildId,
INSERTED.Val,
DELETED.childId,
DELETED.val
;

Hope you have already started to use Merge statement.

My recent blog posts and just learned tips - SQL Server by serverku

Recently I have posted some of the articles and some just learned from the month of October. This article just summarizes all the posts which recently published. You can find the links below to go into the details.

Blog Posts:

• The database owner SID recorded in the master database differs from the database owner SID recorded in database
• Database Backup files Verification and Details
• Grouping Sets vs Native method of Group By - Performance review
• Multi server Query with Central Management Servers
• How to reset SQL Server all default settings in SQL Server Denali CTP3
• Stored Procedure Internal Activation in Service Broker
• New Logical functions coming in SQL Server Denali CTP3
• The ROLLBACK TRANSACTION request has no corresponding BEGIN TRANSACTION
• New String functions arrived by SQL Server Denali CTP3
• Service Broker - Conversation between Databases
• Backup Statistics and History
• NOLOCK Hint & READ UNCOMMITTED Isolation level On table and Query/Session level
• Can not add a shared registered server with the same name as configuration Server
• Database Backup Compression, Amazing feature for DBA
• Review of some replication issues and workaround
• Multi Monitor Support of SSMS

Just Learned tips:

• Script to download file via FTP in SQL Server
• Perform database backup using SQLCMD utility in SQL Server
• Could not connect to server 'RemoteServer' because 'LocalServer' is not defined as a remote server in sql server
• Could not find stored procedure 'sp_MSins_TableName' in replication in sql server
• There is insufficient system memory to run this query
• Change SQL Server instance name
• Adding a transactional pull subscriptions to a publication in replication
• Adding Indexed views in publication for transactional replication
• Adding the transactional publication in Replication
• Enabling the replication database
• Add Functions in publication for transactional replication using tsql script
• Add Stored Procedures in publication for transactional replication using script
• Script to add views in existing publication in transactional replication
• Script to add table in existing publication in transactional replication

Hope these posts help you.

"Can not add a shared registered server with the same name as configuration Server" - Central Management Servers register error in SQL Server 2008 by serverku

You may know how can we register SQL Server instances with Central Management Servers (CMS) and also how can we perform multi server query will all of the instances of registered SQL Server instances.

There you can see I have registered one, shared SQL Server 2011 instance, under CMS and named it Denali. Under Shared instance, I have registered SQL Server 2008 and same SQL Server instance of Denali which I already registered. Here SQL server 2008 successfully registered but SQL Server 2011 has encountered an error. But how I have registered it which I am going to explain here.

This is because the same SQL instance already registered as shared SQL server.

How can i register same SQL Server Denali or 2011 instance again?

I have changed the port and applied static port as follows from SQL Server TCP/IP properties which we will available on the SQL Server Configuration Monitor.

Then please see the screenshot below as I have registered SQL Server Denali instance with port.

Now both SQL Server registered successfully.

Did you get it earlier? How did you resolve?

Database Backup Compression, Amazing feature for DBA - SQL Server 2008 by serverku

Production Database servers may have databases which are heavily in size. For the maintenance of those database backups are very hard and lengthy as the backups of those heavily databases take more time to execute and very CPU, memory and IO consumptive. And the important thing is backups activity should be completed within down time or pick a time when more users are not connected with databases.

What is the solution?
We have alternative ways to use the some backup tool that can help to use in this matter. But SQL Server itself provides the best feature and supported SQL Server 2008 or newer version. That is "Backup Compression". You can read my earlier posts for Automated All Databases Backups, Database Backup files Verification and Details and Split Database Full Backup to Multiple files

Using this feature, we can take a database backup with compression option. And will really reduce the time required to backup it, reduce server IO and less CPU and memory consumption. It is very full features for the DBA. Let us look on below example, which will clear you the difference between the uncompressed and compressed backups. We will first perform non-compressed backups of the database which have 4 GB size.
Using Management Studio :

Using TSQL:

#1. Performing noncompressed backup.

SET STATISTICS IO ON
SET STATISTICS TIME ON

BACKUP DATABASE ReportServer TO  
DISK = N'D:\DBBackups\Compressed\ReportServer_NonCompressedBackup.bak' 
WITH NAME = N'ReportServer-Full NonCompressed Database Backup',
NO_COMPRESSION -- Specifying option here

SET STATISTICS IO OFF
SET STATISTICS TIME OFF
GO

#2. Performing compressed backup.

SET STATISTICS IO ON
SET STATISTICS TIME ON

BACKUP DATABASE ReportServer TO  
DISK = N'D:\DBBackups\Compressed\ReportServer_CompressedBackup.bak' 
WITH NAME = N'ReportServer-Full Compressed Database Backup',
COMPRESSION -- Specifying option here

SET STATISTICS IO OFF
SET STATISTICS TIME OFF
GO

From the result oputput , you can view the time for the backup execution, CPU usage. Here you have screen for the both of the backups size.

You can use below query to get the backup statistics,

SELECT 
 bs.database_name AS DatabaseName , -- Database name
 backup_size/compressed_backup_size as CompressionRatio, 
 CASE bs.type 
  WHEN 'D' THEN 'Full' 
  WHEN 'I' THEN 'Differential' 
  WHEN 'L' THEN 'Log' 
  WHEN 'F' THEN 'File or filegroup' 
  WHEN 'G' THEN 'Differential file' 
  WHEN 'P' THEN 'P' 
  WHEN 'Q' THEN 'Differential partial' 
 END AS BackupType, -- Type of database baclup
 bs.backup_start_date AS BackupstartDate, -- Backup start date
 bs.backup_finish_date AS BackupFinishDate,  -- Backup finish date
 bmf.physical_device_name AS PhysicalDevice, -- baclup Physical localtion
 bs.backup_size AS  [BackupSize(In bytes)],  -- Normal backup size (In bytes)
 compressed_backup_size AS [ConmpressedBackupSize(In bytes)] -- Compressed backup size (In bytes)
FROM msdb.dbo.backupset bs 
INNER JOIN msdb.dbo.backupmediafamily bmf
 ON (bs.media_set_id=bmf.media_set_id)
 AND database_name = 'ReportServer'
ORDER BY bs.backup_start_date DESC

You can set the default backup setting to Compressed as following,

By TSQL :

USE MASTER
GO

EXEC SP_CONFIGURE 'backup compression default', 1
GO
RECONFIGURE WITH OVERRIDE;
GO

From UI :

I hope you like this feature..

Multi Monitor Support of SSMS - A new feature of SQL Server Denali by serverku

I have drafted all the new features and enhancements introduced by SQL Server Denali CTP1 and CTP3.  Multi Monitor Support is the new feature among them.

What can we do?
1. Using this feature we can use multi screen of query analyzer or editor.
2. You can monitor separately it and run the output individually.
3. You can resize all the screens.
4. You can drag and drop at the place you want.
5. You can use Registered servers and object explorer and it's details with multi screens.

For more idea, You can see the below screen shows which I have captured during enjoyed with it.

1. This screen shot has multi screens of query analyzer with SSMS.

2. This screen shot captured during docking/undocking the screens.

Hope you like this post.

Multi server Query with Central Management Servers - SQL Server 2008 by serverku

Before SQL Server 2008, when we need to gather all information and details related to a server or database level, we must run the script individually by connecting each SQL Server instance. But SQL Server 2008 came up and easy our work for that. It has introduced a new feature - Central Management Servers (CMS).

With Central Management Servers we can configure and register SQL Server instances with shared SQL Server instances. Then we run the query against all the SQL instance and get the details for all instances. Let's you demonstrate the same in details here.

1. How to open Central Management Servers?

Go to View --> Registered Servers 
or
press Ctrl + Alt + G.

2. How can register SQL Server instances in CMS?

Expand Database engine from Registered Servers. Right click on the CMS and click on Register SQL Server Management. A new screen will appear below,

In the above, I have registered SQL Server Denali instance, which will be shared SQL Server instance. Now I am creating a new SQL Server Group under CMS and then register SQL Server 2008 and SQL Server 2011 by right click on the group and then go to the link of registration and then go on the same way as I did for SQL Server Denali instance.

3. How can we perform multi server query against all SQL Server ?

Go on right click on Shared SQL Server instance under CMS and click on New Query.

Let's do here same and execute the query and see what will be the result?

This feature very help us to run the script against all the registered SQL Server instances. Hope you liked this post.

New Logical functions coming in SQL Server Denali CTP3 by serverku

As I have started to learn new functions arrived by SQL Server Denali CTP3 version and I have posted some of them. You can learn Analytical functions , Conversion functions and String functions. You can also get the list of all the features coming in SQL Server 2011 CTP3.

Now diverting on this post for the new Logical functions which are following,

1. IIF : It returns one of two arguments, depending on the evaluation of expression. It has require three arguments, first is condition, second and third are the values. Depending on the evaluation of first condition second or third values will be returned, means if the first condition is true, then it will return second value and if it is false then it will return third value. It returns the data type with the highest precedence from the types in true_value and false_value. Let us evaluate it to know it better.

DECLARE @IsDone bit
SET @IsDone = 1
SELECT iif(@IsDone = 1,'Success', 'Failed')
GO

Above code returns "Success". Now les us assign the NULL value to variable then verify.

DECLARE @IsDone bit
SET @IsDone = NULL
SELECT iif(@IsDone = 1,'Success', 'Failed')
GO

Here it returns "Failed" as output. Now elaborate it with more examples.

DECLARE @IsDone bit
DECLARE @FirstVal varchar(10)
DECLARE @SecondVal varchar(10)
SET @IsDone = 1
SET @FirstVal = NULL
SET @SecondVal = NULL

SELECT iif(@IsDone = 1,@FirstVal, @SecondVal)
GO

Above code returns NULL as resulted output. What happen if we pass directly NULL in both first and second values?

DECLARE @IsDone bit
SET @IsDone = 1

SELECT iif(@IsDone = 1,NULL, NULL)
GO

It comes with following error,

"Msg 8133, Level 16, State 1, Line 4
At lease one of the result expressions in a CASE specification must be an expression other than the NULL constant."

Now second turns come for CHOOSE function.

2. CHOOSE : It returns the value at the specified index from among the lists. It has require the first argument as the Index and hen we can pass multiple parameters for the values. It returns the data type with the highest precedence from the set of types passed to the function. Let elaborate it with sample examples.

DECLARE @Index int
SET @Index = 2

SELECT CHOOSE (@Index,'First','Second','Third')
GO

It returns "Second" value because it belongs to the second index.

DECLARE @Index int
SET @Index = 0

SELECT CHOOSE (@Index,'First','Second','Third')
GO

Above query returns NULL as output.

DECLARE @Index int
SET @Index = NULL

SELECT CHOOSE (@Index,'First','Second','Third')
GO

Same as earlier query it also returns NULL as resulted output. What happen if we pass all the values with NULL?

DECLARE @Index int
SET @Index = 2

SELECT CHOOSE (@Index,NULL,NULL,NULL)
GO

It's also come up with a NULL. Hope you liked these functions. Stay tuned for more posts.