SCD Type 1 with example

SCD Type 1:

In this method the new record will replace the old record and there is no tracking for history.

Example:

In the below table we have an employee named as Anil bearing the the EID 503 and Address as JNTU. Same details reflected in target table/warehouse table. 

Source table: 

Target Table:

Now we have updated the Address JNTU as KPHB for the employee Anil. In this SCD Tpye 1 there is no history tracking, so it will update the target table record with new value.

Below is the updated target table.

Advanteges:

• This is the most simple way to implement SCD in our warehouse, because we no need to store the previous details.

Disadvantages:

• We will loose all the previous history and not possible to track the previous details. In above example, once the target table data updated, the employer couldn't find the previous address of the employee Anil. This is the major disadvantage in SCD Type1.

If we are sure, there is no need to maintain the history of the dimension table, then we can go for this SCD Type1 method.

Please leave a comment, if you have any question or need any clarifications. 

What is SCD and Types of SCD

What is Slowly Changing Dimension:

Slowly changing dimension used to determine, how the historical changes are handled in warehouse tables.
Consider an example, where the employee address is being changed and the employer want to keep the previous address of the employee, that is the situation where SCD comes into picture. we will discuss in detail about SCD in types of SCD.

Types of SCD:

There are mainly 3 types of slowly changing techniques are there. Please click on them to explore.

SCD Type 1

SCD Type 2

SCD Type 3

ODI 11g Installation on windows 7 64 bit

Before we are going to install ODI 11g, we should create the repositories by using RCU (Repository configuration utility).

Repositories creation by using RCU :

Download the RCU setup file from OTN and extract it.

Double click on the RCU file

Please click on the next.

This is the very first time, we are going to create the repositories, so select the Create radio button and click on next.

Provide your database connection details, where you want to create your schemas( repositories)

Click on ignore and proceed.

it will automatically check for the prerequisites. click on OK.

Please select prefix as your wish, here I selected prefix as DEV.
And choose the oracle data integrator.

click on ok.

Provide the proper details as shown in below.

Once you provided the Password and other details click on Next.

Click Next.

Click on OK.

RCU creating the required table spaces.

Click on Create.

Now we are done with repository creation for ODI 11G.

DAC 11G Configuration steps on windows 7

After successful installation of DAC. We need to configure DAC to work properly.

Click on DAC client.

Click on Configure button.

Choose the Create Connection radio button.

Enter the proper details as shown in above.

When click on Authentication file, choose create a new authentication file as shown in above.

Provide the destination path and click on ok.

Provide the proper credentials to generate an Encryption key. click on Generate Random Encryption Key.

Please note down that encryption key, will be useful in further steps.

Click on Test connection.

we have successfully established the connection.

Then again click on DAC client and provide the valid login details. Choose authentication type as DAC.

Provide the tables space if you want, otherwise click on OK.

Please provide your DAC repository user, which we have created early. Click on OK

Give the user name and password as administrator.

That's all !!! we are done with DAC configuration. Just we need to start the server and create containers and play with that all. :) :)