Tag Archives: SQL

EOMONTH() – End of the month – SQL Server 2012

So how do we calculate the last date of the month which is 4 months from now?

SQL Server 2012 presents EOMONTH() function. Let us understand this function with an example.

DECLARE @MyDate datetime
SET @MyDate = GETDATE()
SELECT EOMONTH (@MyDate,4)
SELECT EOMONTH (@MyDate,-4)
as LastDayOfTheMonth

eom2
So what do we find from the 2 outputs. Well it gives me the last date of the 4th month from the current month i.e. 4 months from now would be April and the last date of April is 30th. The second output gives the last date of 4 months previous i.e August. This function would be very handy in calculations where the last date of the month is a critical factor. Previously to achieve this we would have to do a bit of manipulation.

Pagination – Using OFFSET and FETCH in SQL Server 2012

OFFSET and FETCH are two new clauses introduced in SQL Server 2012 that allows us to extract a portion of rows from the result set. When we need to display a large result set to the user, the best way of going about it is to split them .i.e use pagination. In SQL Server 2012, we can achieve pagination by using the ‘OFFSET’ and ‘FETCH’ commands. Let us understand this with an example:

USE AdventureWorks2012
GO
SELECT pp.ProductId,PP.Name,pp.ProductNumber,
pp.DaysToManufacture,pp.ListPrice
FROM Production.Product PP
ORDER BY pp.productid

OandF1
The query returns 504 rows as depicted above. So what do i do if i need to fetch only a portion of the above rows?

Enter OFFSET and FETCH. How? let us understand this with an example

USE AdventureWorks2012
GO
SELECT PP.ProductID,PP.Name,pp.ProductNumber,
pp.DaysToManufacture,pp.ListPrice
FROM Production.Product PP
ORDER BY pp.ProductID
OFFSET 100 ROWS
FETCH NEXT 10 ROWS ONLY

OandF2Here, the OFFSET tells the query to ignore the first 100 rows and then return only the following 10 rows. This is very easy to use and a quick way to return just a portion of records.
Few Limitations of the OFFSET and FETCH clause as stated in msdn:
a) ORDER BY is mandatory to use OFFSET and FETCH clause.
b) OFFSET clause is mandatory with FETCH. You can never use, ORDER BY … FETCH.
c) TOP cannot be combined with OFFSET and FETCH in the same query expression.
d) The OFFSET/FETCH row count expression can be any arithmetic, constant, or parameter expression that will return an integer value. The row count expression does not support scalar sub-queries.

TRY_PARSE – Conversion function in SQL Server 2012

In this article I will discuss about the TRY_PARSE function in SQL Server 2012. Conversion functions helps us avoid errors when dealing with different data types. Let us understand TRY_PARSE with an example.

SELECT TRY_PARSE ('12-18-2013' AS datetime) AS Alpha
SELECT TRY_PARSE ('2013' AS decimal) AS Beta
SELECT TRY_PARSE ('2013.00' AS decimal) AS Gamma
SELECT TRY_PARSE ('2013.0000' AS float) AS Theta
SELECT TRY_PARSE ('Arsenal' AS float) AS Delta

The TRY_PARSE() function can convert any string value to a Numeric or Date/Time format. If the passed string value cannot be converted to Numeric or Date/Time format, it will result to a NULL.

Lets have a look at the output of the above
TP2In the above case it would not convert ‘Arsenal’ to a date time or Numeric value and hence it results in NULL output. TRY_PARSE function is not a native SQL SERVER function, instead it is a CLR dependent function.

IIF – The InLine conditional Statement in SQL Server 2012

IIF is a new inline conditional statement in SQL Server. We can pass an expression that can be evaluated to either true or false to the function and it returns one value for true and another one for false.

Let us understand this with an example:

DECLARE @MyTeam nvarchar(40) = 'Manchester United'
DECLARE @YourTeam nvarchar(40) = 'Arsenal'
SELECT IIF (@MyTeam = @YourTeam, 'True Devils',
'False Gooners') AS YouAre

The output of the above as below. In this we have passed two different values.
IIF1Now let us pass two same values and see how this works:

DECLARE @MyTeam nvarchar(40) = 'Manchester United'
DECLARE @YourTeam nvarchar(40) = 'Manchester United'
SELECT IIF (@MyTeam = @YourTeam, 'True Devils',
'False Gooners') AS YouAre

IIF2
IIF is very useful where a straightforward comparison has to be made without writing case statements.

How to use ‘WITH RESULT SETS’ in SQL Server 2012

In SQL Server 2012, the execute statement has been enhanced with an option called ‘WITH RESULT SETS‘. So let us understand what this does.

This option enables us to change the column names and data types of the returning result set from the stored procedure. Let us understand this with an example.

Create a new stored procedure

USE AdventureWorks2012
go
CREATE PROC Usp_products
AS
SELECT ProductID,Name,ProductNumber FROM Production.Product
ORDER BY ProductID

Let us now execute the above procedure and see the outcome
withresultset1Now let us use this new option and change the name of the columns and their data types while the procedure returns the output at run time.

EXEC Usp_products
WITH RESULT SETS
(
(
SerialNumber varchar(15),
Name1 varchar(30),
ProductNumber1 varchar(30)
)
)

withresultset2So this is how we can use this option to tweak the output set to different data types and column names from an stored procedure.

Resources in a SQL Server Failover Cluster

In this article I will discuss about the resources that are part of a SQL Server failover cluster.

A SQL Server failover cluster instance consists of 2 kinds of resources.

1)Local Resources: Local resources are those components that are installed on each possible owner node. They remain on that node and do not move over during a failover.
2)The shared resources: Those resources that fail over between the owner nodes.

Let us now go through the resources that are part of a resource group in a SQL Server failover cluster.
a) SQL Server Database Engine\Agent service : The database engine and SQL Server agent resources are always part of any SQL Server failover cluster’s resource group where the database engine has been installed. If SQL server analysis service is installed, then it will be a part of the resource group. From an availability and performance perspective it is better if both are installed on separate resource groups.

b) IP Address and Network name: The IP address and network name component ensures an interface that clients can use to connect to the SQL Server instance  irrespective of the fact that which node is currently serving the cluster. During a failover event,  the network name and IP addresses is registered to redirect to the new node that is serving the SQL Server failover cluster instance. To the clients that are connecting to the SQL Server, this is a absolutely transparent process.

c) Shared disks:A SQL Server shared disk contains all of the system and user data including databases, logs for the SQL Server failover cluster instance. When a failover occurs, the disks are mounted on the new node. When SQL Server instance is started on the new node, it goes through recovery as part of the SQL Server startup and maintains access to the same database files that existed when it was running on the previous node.The shared disks are the single point of failure for a failover cluster instance. Windows Server and SQL Server failover clustering provides redundancy for machines, operating systems, and SQL Server binaries, but requires reliable storage to assure availability of the shared storage.

Format() function in SQL Server 2012

SQL Server 2012 introduces this new function called FORMAT which returns a value in the specified format and also can optionally apply a regional format. This function relies on the .NET Framework.

In this article we will explore this function and see how it can be implemented.

FORMAT() accepts 3 parameters. The first parameter is the VALUE parameter where we pass on the date value or a numeric value. The second parameter is the .NET Framework format string. The format parameter is case sensitive. The third parameter is the culture. This can be any culture supported by the .NET Framework.

Let us now explore this function with some examples:
1) Display the date using Bengali Culture

DECLARE @date DATETIME = '12/04/2013';
SELECT FORMAT ( @date, 'MMMM dddd dd yyyy', 'Bn-IN' )
 AS DateInBangla;

format12) Display the date using Tamil Culture

DECLARE @date DATETIME = '12/04/2013';
SELECT FORMAT ( @date, 'MMMM dddd dd yyyy', 'Ta-IN' ) AS
DateInTamil;

format23) Display an amount into different currency structures

SELECT FORMAT(100, 'C', 'en-GB') AS Pounds,
FORMAT(100, 'C', 'en-US') AS Dollars,
FORMAT(100, 'C', 'es-ES') AS Euro,
FORMAT(100, 'C', 'en-IN') AS Rs;
GO

format34) Display current date time in US format

SELECT FORMAT(GETDATE(), N'"Time now is "dddd MMMM dd, yyyy', 'en-US')
AS USTimeStamp;

format4For more details on this function please refer to this msdn link.

What is C2 Audit tracing in SQL Server

In this article I will discuss the C2 audit trace option in SQL Server.C2 is security-auditing level defined by the US Government’s Trusted Computer Security Evaluation Criteria (TCSEC) program. Microsoft added the C2 audit mode option to address government requirements that certain contractors document database activity and possible security policy violations. So what does this audit trace do and how can we enable\disable the audit trace.

This audit captures the following information on the SQL server.
1) End User Activity (All SQL commands, logins and logouts)
2) Security Events (Grant/Revoke/Deny, login/user/role add/remove/configure)
3) Utility Events (Backup/Restore/ Bulk Insert/BCP/DBCC commands)
4) Server Events (Shutdown, Pause, Start)

Let us now see how we can enable this audit trace
Step 1: Run the below code

EXEC sys.sp_configure N'c2 audit mode', N'1'
GO
RECONFIGURE WITH OVERRIDE
GO

Step 2: Restart the SQL Server

Once you have restarted the SQL Server, you will find a new trace has kicked off. If you run sys.traces on the server you will find an audit trace that is running
c2If you browse to the location of the trace and open the trace file and view the properties of the trace then you will see as below
c2_1So how can we stop this trace. If we try the traditional way of stopping a trace then it will result in an error. Snapshot below.
C2_3Follow the below steps to stop this trace and remove its definition from the server
Step 1: Run the below code

EXEC sys.sp_configure N'c2 audit mode', N'0'
GO
RECONFIGURE WITH OVERRIDE
GO

Step 2: Restart the SQL server

Few important points that we have to keep in mind before implementing this audit trace
1) This is resource consuming . Implement with caution on a busy OLTP system.
2) The max size of the trace file is set to 200 Mb. You cannot change this.
3) Once the size is breached, a new trace file generated.
4) If the directory in which logs are being saved runs out of space, SQL Server will shut itself down. If auditing is set to start automatically, you must either restart the instance with the -f flag, or free up additional disk space for the audit log.
5) You cannot filter out events from this trace property, it captures everything.

CONCAT() function in SQL Server 2012

In this article I will discuss the new function concat() in SQL Server 2012. This function performs a concatenation operation. We need to pass CONCAT() a number of string arguments and it will concatenate, or join them together and return an output string.
The basic syntax is as follows:
CONCAT ( string_value1, string_value2 [, string_valueN ] )

Let us now understand with an example how we can use this function and how it is different from the concatenation operator. Let us create a new table and insert some values in the table and then use a query that will use this function

CREATE TABLE MyConcatTable
(
FirstName varchar(20) NOT NULL,
MiddleName varchar(20) NULL,
LastName varchar(20) NOT NULL
)
INSERT INTO MyConcatTable
VALUES
('Sachin', 'Ramesh', 'Tendulkar'),
('Diego', 'Armando', 'Maradona')
,('Diego', Null, 'Maradona')
SELECT CONCAT(FirstName + ' ', MiddleName + ' ', LastName) AS
CustomerName
FROM MyConcatTable

The output of the above as shown below
concat1The concat function joins the columns and returns a single string. Now the big question is how is it different from the below

SELECT FirstName + ' ' + MiddleName + ' ' + LastName AS CustomerName
FROM MyConcatTable

Let us run the above code and see the outcome
concat2The 3rd value in the table has a null in the middle name column. Normal concatenation would not handle that thus resulting in a null output but the concat() would automatically remove the null and join the next corresponding string value.

I hope this short article was helpful in understanding the new function in SQL Server 2012 called concat().

Life is a SEQUENCE of events – Part 2

In my previous article on Sequence we went through how we can create and implement Sequence.In this short article I will demonstrate how we can achieve the following:

1) How to get the current value of the Sequence
2) How to get the next Sequence Value
3) Restarting the Sequence Value
4) Dropping a Sequence object

1) current value of the Sequence
To find the current value of a Sequence we need to query the system view sys.sequences.

USE AdventureWorks2012
go
SELECT Current_Value FROM sys.sequences
WHERE name= 'MySequence1' -- specify the name of the sequence
GO

2) get the next Sequence Value:

use Adventureworks
go
SELECT (NEXT VALUE FOR MySequence1)
AS NextSequenceValue

3) Restarting the Sequence Value:

USE [AdventureWorks2012]
GO
ALTER SEQUENCE [dbo].[MySequence1]
RESTART  WITH 100001
INCREMENT BY 10
NO MINVALUE
MAXVALUE 200000

4) Dropping a Sequence object:

use Adventureworks2012
go
DROP SEQUENCE MySequence1;
go

How to restore a table from a Full backup using Quest Litespeed without restoring the entire database

In this article I will demonstrate how we can restore a table from a SQL Server database backup file which has been taken by Quest Litespeed tool. This feature called Object level recovery in the tool is extremely helpful as you need not restore the entire database and yet retrieve data from the backup. Follow the below mentioned steps and understand how this can be accomplished. I will be using a trial copy of Quest Litespeed along with SQL server 2012 and the database we would use is Adventureworks2012. However you can use SQL server 2008 also.

Step 1: Create a database and take a full backup of the database
Let us create a database for this purpose

CREATE DATABASE MyDB
GO
USE mydb
GO
CREATE TABLE Mytable1
( id INT,FNAME NVARCHAR(50) )
GO
INSERT INTO Mytable1 VALUES (1,'Sanchayan')
GO
INSERT INTO Mytable1 VALUES (2,'Abhishek')
go
CREATE TABLE Mytable2
( id INT,LNAME NVARCHAR(50) )
GO
INSERT INTO Mytable2 VALUES (1,'Pandit')
GO
INSERT INTO Mytable2 VALUES (2,'Agrawal')
go

Now take a Full Backup of the database.

exec master.dbo.xp_backup_database
@database = N'Mydb',
@compressionlevel = 3,
@filename = N'D:\MSSQL\SQLBackup\Mydb.bak',
@init = 0,
@OLRMAP = 1--This is important as this marks the backup for object level recovery
GO

Step 2: Now run the following code to find the Tables available in the backup

Use Master
go
exec xp_objectrecovery_viewcontents
@FileName = N'D:\MSSQL\SQLBackup\mydb.bak',
@FileNumber = 1,
@Type = 'All',
@DisableLogProcessing = 1

olr1
Step 3: Now select the table that you wish to restore. In this demo we would restore MyTable2.
We would need the below predefined:
a) The database where we would restore the table.
b) A temp directory location which should be large enough for the table to be restored initially.

Use master
go
exec xp_objectrecovery
@FileName = N'D:\MSSQL\SQLBackup\Mydb.bak',
@FileNumber = 1,
@ObjectName = N'dbo.Mytable2',
@DestinationTable = N'[dbo].[Mytable2]',
@DestinationDatabase = N'MyTempDB',
@DestinationServer = N'GN-A-MOOKBO-7L\sql2012',
@TempDirectory = N'D:\MSSQL\SQLBackup',
@DisableLogProcessing = 1

The output of the above code would be as below
olr2To verify if the data you can query the table that we restored on mytempdb database
olr3I hope this article was helpful in understanding how we can use ‘Object level recovery’ to fetch data from a full backup file that has been taken using Quest Litespeed for SQL Server tool.

Technical reference: http://www.quest.com/litespeed-for-sql-server/

How to find the last execution details of a stored procedure in SQL Server

In this article I will demonstrate how we can find the last execution details of a stored procedure in SQL Server 2012 or SQL Server 2008 R2.With DMV’s getting modified in these 2 editions of SQL Server, the amount of information we can obtain from the plan cache can be handy for investigation purpose.
When a stored procedure is created or recompiled, a plan for the same is created and cached in the plan cache. Whenever the same stored procedure is executed, the plan is recalled from the SQL memory for execution purpose. The details of an execution is stored internally in SQL Server which can be fetched via the dynamic management views.

A key element in this process is that the plan has to be in the plan cache for us to derive the information. By any chance if the SQL Server gets restarted or the plan cache is cleared then the information would not be available.

Let us see how we can fetch the execution details with an example. I have used the Adventureworks2012 database for demonstration purpose
SQL Server 2012:
Execute the below mentioned SP on SQL Server 2012

USE [AdventureWorks2012]
GO
EXEC [dbo].[uspGetEmployeeManagers] @BusinessEntityID = 135

The execution produces 4 rows
ED1Now let us find the execution details of this stored procedure from the plan cache. Open another Query editor and execute the below mentioned query. The query searches the plan cache for the execution details of the stored procedure, whose name we have filtered in the last line of the query

SELECT qs.sql_handle,qs.creation_time,qs.last_execution_time,
qp.dbid,qs.execution_count,qs.last_rows,qs.last_logical_reads,
qs.last_logical_writes,qs.last_physical_reads,st.text
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY
sys.dm_exec_sql_text(qs.sql_handle)AS st
CROSS APPLY
sys.dm_exec_text_query_plan(qs.plan_handle,DEFAULT,DEFAULT) AS qp
WHERE st.text like '%USPGET%'---filter by name of the SP

The output would be as follows:
ED2Now if we observe the outcome we would find the following information very handy
1. Last execution Time
2. Execution Count
3. Last_rows: This depicts the number of rows as output when the SP executed last.
4. Last_Logical_Reads
5. Last_Logical_Writes
6. Last_Physical_Reads

In SQL Server 2008 R2, the column that would be missing is Last_rows. So the query that you can use in SQL Server 2008 R2 would be as below

SELECT qs.sql_handle,qs.creation_time,
qs.last_execution_time,
qp.dbid,qs.execution_count,qs.last_logical_reads,
qs.last_logical_writes,qs.last_physical_reads,st.text
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY
sys.dm_exec_sql_text(qs.sql_handle)AS st
CROSS APPLY
sys.dm_exec_text_query_plan(qs.plan_handle,DEFAULT,DEFAULT)AS qp
WHERE st.text like '%Name of Stored Proc%'

Find the Buffer Pool usage per database in SQL Server

In this short article i will share a simple query that i wrote to find the number of pages of a database in the buffer pool and there usage of the buffer pool

SELECT CASE database_id WHEN 32767 THEN 'ResourceDb'
ELSE DB_NAME(database_id)
END AS [Database],COUNT(*) AS PageCount ,
( COUNT(*) * 8.0 ) / 1024 AS [SpaceOccupiedInBuffer-Mb]
FROM sys.dm_os_buffer_descriptors
GROUP BY database_id
ORDER BY 3 DESC

BF1

How to find and remove a query plan from the plan cache in SQL Server

In this article I will try to explain how we can obtain the plan of a SQL query from the plan cache and also how we can remove the plan from the cache keeping other plans intact. Before we see how we can achieve the above we will understand few basic things on plan cache.
Structure
1) What is a query plan: A query plan is an organized and ordered set of steps used by the SQL engine to fetch data. Every query has a query plan cached in the SQL memory
2) What is a plan cache: Apart from Buffer pool which is the biggest consumer of SQL Server memory, SQL Server allocates a proportion of this memory for use of storing the query plans. This storage of query plans in the SQL memory is called plan cache. The storage is a volatile storage and if the SQL server is restarted then all the plans are removed from this cache.
3) What is a plan handle: A plan handle is an unique identifier of the plan.

Let us now see how we can locate the query plan of an already executed query:
Step 1: In this example I have executed the below query on the Adventureworks2012 database.

SELECT [BusinessEntityID],[Title]
,[FirstName],[MiddleName]
,[LastName],[Suffix]
,[JobTitle],[PhoneNumber]
,[PhoneNumberType],[EmailAddress]
,[EmailPromotion],[AddressLine1]
,[AddressLine2],[City]
,[StateProvinceName],[PostalCode]
,[CountryRegionName],[AdditionalContactInfo]
FROM [AdventureWorks2012].[HumanResources].[vEmployee]
WHERE PostalCode = '98104'

Step 2: Now let us find the query in the plan cache. We will use the below query to find the plan of the query from the plan cache. Observe carefully that in line number 11 we have used a filter to search all the queries in the plan cache which has the word ‘PostalCode’ which is also a part of our executed code on the Adventureworks2012 database.

select a.plan_handle,query_plan,text,
execution_count,size_in_bytes,
creation_time,usecounts,
last_execution_time,execution_count,
total_elapsed_time,last_elapsed_time
from sys.dm_exec_cached_plans a
inner join sys.dm_exec_query_stats b
on a.plan_handle=b.plan_handle
cross apply sys.dm_exec_sql_text(b.sql_handle) as sql_text
cross apply sys.dm_exec_query_plan(a.plan_handle) as query_plan
where text LIKE '%PostalCode%'

Snapshot of the output below
Qp1
Step 3: The highlighted text is the query that we ran and you can see the the query plan associated with it on the second column. Click on the plan and it will open on a new window.
qp2
qp3
So now we know how we can find the plan of an already executed query from the cache. In short use the above mentioned query and use a string from the executed query as filter in the above given query.

Now let us see how we can remove the query plan from the plan cache
Step 1: Find the plan handle of the query plan.
qp4
Step 2: Execute the below code to drop the plan from the plan cache

DBCC freeproccache(0x06000100A8CEE12640BB20D50200000001000000000000000000000000000000000000000000000000000000)

This will only drop that particular plan from the plan cache.Be very careful that you do not practice this on a production environment without understanding the implications of the absence of the query plan which you dropped.

I hope this article was helpful in finding and removing query plans from the plan cache without impacting other plans.

How to Remove Table Partitioning in SQL Server

In this article we will see how we can remove partitions from a table in a database in SQL server. In my previous post i had demonstrated how we can partition a table via T-SQL. Lets now remove the partitions and merge the data in a single partition. I will start from where we left off in my previous post of partitioning a table.

1) Run the below code to create a database named PartitionDB that would include a table that has been partitioned.

USE master
GO
CREATE DATABASE PartitionDB
ON PRIMARY (NAME = N'PartitionDB'
,FILENAME = N'D:\MSSQL\Data\PartitionDB.mdf'
,SIZE = 50MB, FILEGROWTH = 150MB)
LOG ON (
NAME = N'PartitionDB_log'
,FILENAME = N'D:\MSSQL\Logs\PartitionDB_log.ldf'
,SIZE = 10MB, FILEGROWTH = 100MB);
GO

ALTER DATABASE PartitionDB ADD FILEGROUP PartitionFG1;
GO
ALTER DATABASE PartitionDB ADD FILEGROUP PartitionFG2;
GO
ALTER DATABASE PartitionDB ADD FILEGROUP PartitionFG3;
GO
ALTER DATABASE PartitionDB ADD FILEGROUP PartitionFG4;
GO

ALTER DATABASE PartitionDB
    ADD FILE
    (
        NAME = PartitionFile1,
        FILENAME = 'D:\MSSQL\Data\PartitionFile1.ndf',
        SIZE = 20MB, MAXSIZE = 50MB, FILEGROWTH = 5MB
    )
    TO FILEGROUP PartitionFG1;
GO

ALTER DATABASE PartitionDB
    ADD FILE
    (
        NAME = PartitionFile2,
        FILENAME = 'D:\MSSQL\Data\PartitionFile2.ndf',
        SIZE = 20MB, MAXSIZE = 50MB, FILEGROWTH = 5MB
    )
    TO FILEGROUP PartitionFG2;
GO

ALTER DATABASE PartitionDB
    ADD FILE
    (
        NAME = PartitionFile3,
        FILENAME = 'D:\MSSQL\Data\PartitionFile3.ndf',
        SIZE = 20MB, MAXSIZE = 50MB, FILEGROWTH = 5MB
    )
    TO FILEGROUP PartitionFG3;
GO

ALTER DATABASE PartitionDB
    ADD FILE
    (
        NAME = PartitionFile4,
        FILENAME = 'D:\MSSQL\Data\PartitionFile4.ndf',
        SIZE = 20MB, MAXSIZE = 50MB, FILEGROWTH = 5MB
    )
    TO FILEGROUP PartitionFG4;
GO

CREATE PARTITION FUNCTION PartFunc1 (int)
    AS RANGE LEFT FOR VALUES (10, 20, 30);
GO

CREATE PARTITION SCHEME PartScheme1
    AS PARTITION PartFunc1
    TO (PartitionFG1, PartitionFG2,PartitionFG3,PartitionFG4);
GO

USE [PartitionDB]
GO
CREATE TABLE PartitionTable
    (
    MyID int NOT NULL,
    MyDate datetime NULL,
    Name varchar(50) NULL
    )  ON PartScheme1(MyID)
GO
USE PartitionDB
go
CREATE UNIQUE CLUSTERED INDEX IX_PartitionTable
ON PartitionTable(MyID)
ON PartScheme1 (MyID);
GO

USE PartitionDB
go
INSERT INTO PartitionTable (MyID, MyDate,name)
VALUES (1,GETDATE(),'Rooney');
INSERT INTO PartitionTable (MyID, MyDate,name)
VALUES (11,GETDATE(),'Van persie');
INSERT INTO PartitionTable (MyID, MyDate,name)
VALUES (22,GETDATE(),'De Gea');
INSERT INTO PartitionTable (MyID, MyDate,name)
VALUES (34,GETDATE(),'Moyes');
GO

Run the below code to see the details of the partitioned table

USE PartitionDB
GO
SELECT
OBJECT_NAME(idx.object_id) AS TableName ,
psh.name AS PartitionSchemeName ,
fnc.name AS PartitionFunctionName,
part.partition_number AS PartitionNumber ,
fg.name AS [Filegroup],
rows AS 'No of Records' ,
CASE boundary_value_on_right WHEN 1 THEN 'less than'
ELSE 'less than or equal to' END AS 'Condition',
value AS 'Range' ,
part.partition_id AS [Partition Id] FROM sys.partitions part
JOIN sys.indexes idx
ON part.object_id = idx.object_id
AND part.index_id = idx.index_id JOIN sys.partition_schemes psh
ON psh.data_space_id = idx.data_space_id
JOIN
sys.partition_functions fnc
ON fnc.function_id = psh.function_id LEFT
JOIN sys.partition_range_values prv
ON fnc.function_id = prv.function_id
AND part.partition_number = prv.boundary_id
JOIN sys.destination_data_spaces dds
ON dds.partition_scheme_id = psh.data_space_id
AND dds.destination_id = part.partition_number
JOIN sys.filegroups fg
ON dds.data_space_id = fg.data_space_id
JOIN (SELECT container_id, sum(total_pages) as total_pages
FROM
sys.allocation_units GROUP BY container_id) AS au
ON au.container_id = part.partition_id JOIN sys.tables t ON
part.object_id = t.object_id WHERE idx.index_id < 2
ORDER BY TableName,part.partition_number;
GO

Now let us understand how we can remove the partitions from this table.
The easiest way to do this is to drop the Clustered index from this table and recreate it on another filegroup.

Step 1: Drop the clustered index from the table

USE [PartitionDB]
GO
DROP INDEX [IX_PartitionTable] ON
[dbo].[PartitionTable] WITH ( ONLINE = OFF )
GO

Step 2: Re-create the clustered index on another Filegroup. We will use the primary FG as example

USE [PartitionDB]
GO
CREATE UNIQUE CLUSTERED INDEX [IX_PartitionTable] ON
[dbo].[PartitionTable]
(
 [MyID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF,
SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF,
DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON)
ON [PRIMARY]
GO

Step 3: Verify the state of the partitions by running the below code. You will find that there is only one partition with all the 4 rows in it.

USE PartitionDB
go
SELECT * FROM sys.partitions
WHERE OBJECT_NAME(OBJECT_ID)='partitiontable';
GO

P3You can verify the same via SSMS by performing the following steps:
Step 1: Right click on the table
Step 2: Click on properties
Step 3: Click on Storage
Step 4 : Verify that “Table is partitioned” is false.
P4I hope this article was helpful in understanding how we can remove Partitioning from table.

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