Cluster Index - Always logical ordering sometimes physical ordering

IF Object_id('T1') is NOT NULL
DROP TABLE T1
Go
CREATE TABLE T1(Name varchar(20))
Go
INSERT T1 (Name) values ('Apple'),('Boy'), ('Dog'),('Elephant')

GO
SELECT * From T1

CREATE CLUSTERED INDEX CINDX_T1 ON T1(NAME)

/*
1 – data page

2 – index page

3 and 4 – text pages

8 – GAM page

9 – SGAM page

10 – IAM page

11 – PFS page
*/

DBCC IND('SQLCommitted',T1,-1)

/*
dbcc page ( {‘dbname’ | dbid}, filenum, pagenum [, printopt={0|1|2|3} ])
*/
DBCC TRACEON (3604);

DBCC PAGE ('SQLCommitted', 1,668, 1)

INSERT T1 (Name) values ('Cat')

DBCC PAGE ('SQLCommitted', 1,664, 1)

DBCC PAGE ('SQLCommitted', 1,664, 2)

ALTER TABLE T1 REBUILD

DBCC IND('SQLCommitted',T1,-1)

DBCC PAGE ('SQLCommitted', 1,664, 1)

DBCC PAGE ('SQLCommitted', 1,664, 2)

Comments

UML - Association, Aggregation, Composition, Generalization, Specialization, Realization and Dependency

Association Association is a simple relationship between two classes. For example A relationship between Professor Class and Student class is known as Association. Both Classes can exist without each other, so Professor and Student are two independent classes. In this kind of relationships there will not be any owner class. Both classes have their own life cycle. UML Notation: Aggregation Aggregation is a special type of Association. It is known as “Has-A” relationship. For example A Department class can contain Professor Class. Here Department class is owner class. Here in this relationship even after deleting Department class, Professor Class can exits. UML Notation: Composition Composition is a special type of Aggregation. It is known as “Is-A” relationship. For example A University Class has many Department class. Here University and Department objects are dependent on each other. If we delete Univ...

C# Generic Factory

Implement Factory pattern using generics public interface IDoWork { string DoWork(); } Declare an Interface first by abstracting the common functionality Here I am taking the example of DoWork public class Manager : IDoWork { public string DoWork() { return "Manager Manages School" ; } } Implement the IDoWork in concrete classes as shown public class Teacher : IDoWork { public string DoWork() { return "Teacher teaches student in school" ; ...

SSIS package - set oledb connections at runtime

SSIS oledb connection manager does't allow user to connect to different oledb servers. If we store oledb connection sting in Config file then it will accepts server name, InitialCatalog and username. But it wont accept password. The is because oledb connection manager has not exposed the oledb password property. To over come this problem we have to override the OLEDB connection manager itself. So that it accepts connections to different oledb servers. Public Sub Main() Dim vars As Variables Dim oledbConnectionManager As ConnectionManager oledbConnectionManager = Dts.Connections("<oledb connection name>") ' ADDED TO MAKE oledb CONNECTION STRING DYNAMIC Dim oServerName As String Dim oUserName As String Dim oInitialCatalog As String Dim oPassword As String Dts.VariableDispenser.LockOneForWrite("oServerName", vars) oServerName = vars("oServerName").Value.ToString().Trim() vars.Unlock() Dts.VariableDispenser.LockOneForWrite("oInitia...

Prime Instance

Search This Blog