SCD Type 1 and Type 2 using SQL | Implementation of Slowly Changing Dimensions

[@macx8360]

you wont believe ,i was just learning the same concept from your python course today itself in the morning

[@Nalaka-Wanniarachchi]

Great stuff.Must learn one by every data enthusiast.

[@RoamingSoming]

Great way of explaining SCD types

[@subhajitdey6806]

great video ! need more data modelling and data engineering videos man !

[@shanthiprabhu2100]

Great Ankit, thanks. I am completely new to this concept and its very useful

[@ashanair5909]

If there was a way to love your videos and not just like.. Learning a lot Ankit. Thanks

[@ankitbansal6]

Cheers 🥂

[@sravankumar1767]

Superb explanation 👌 👏 👍

[@Sachin_Sambare]

you are too good..very very nice explanation

[@ankitbansal6]

Thank you for the appreciation

[@ankitbhangdia3931]

@ankit bansal: Great job on explaining the concept. qq: Instead of making the end date as forever, will it make sense to keep it as NULL & include another column such as is_current_value which would be a boolean field. When someone wants to track the history in the report, an analyst can simply put the condition for start_date, end_date IS NULL and is_current_value = 'n' to take a look at the previous record or they could query on the start_date, end_date IS NOT NULL and is_current_value ='y'. You could even use an OR operator in the query with the structure I'm proposing. Using forever as the end_date is frowned upon in the data warehousing world IMHO.

[@JuanHernandez-pf6yg]

Very useful. Thank you!

[@deepakj6717]

Best video.. Thanks !! If possible pls make videos on SQL performance tuning or launch course.

[@uditkapadia7104]

Great Explanation !

[@meropahad7537]

Thanks for the video Ankit

[@apexemperor]

Needed this video but 6months ago... Bt we did it together in office with a friend that time 😀😺 using sql

[@yuvrajyuvas4730]

Awesome Bro..

[@pradeepyogesh4481]

Very good information and thanks for the content. How to create staging tables in the first place?

[@aadil8409]

sir, can we implement scd-1 via merge statement. i mean to ask is merge statement is nothing but the scd-1 only?

[@Ironsouljourney]

my question is if we connect the data in power bi desktop so we need to manually do this scd 2 or it will automatically updated

[@vamsivamsi2029]

Thanks @ankit

[@chaitanyanagare757]

In SCD1 when first insert is completed we emptied the stg table.. How can we do changed to update dim without empty the stg after first insert

[@milindzuge906]

Thank you so much Ankit ❤😊

[@ankitbansal6]

My pleasure 😊

[@srinubathina7191]

Thank you Ankit Bro

[@typing07]

@ankit Bhaiya, Instead of doing manual work by query, We can create insert update trigger also, that will be a good automation work. What you say brother.☺

[@ankitbansal6]

That will be too much load because it will trigger for each row.

[@nehashahpatel1741]

Million Thanks

[@anikethdeshpande8336]

Hi Ankit, great explanation, how to handle scenario in scd2 type two, when there are insert, update and delete all together in staging for the same record. Assuming we are using cdc to keep track of changes and using cdc info to update the dim tables

[@sandeepguptha6440]

then you need to create one more temp_table while running script by keeping where timestamp in stg_table > max(timestamp) in dim_table to get the only changed records to temp_stg table now data is in temp_table (which has only latest records) dim_table has old records as of now (we did not performed any transformations yet) now follow anikt procedure to keep history track

[@chinmayaMuduli-kf3dd]

Hi Ankit sir will you start any data engineering course ?

[@007SAMRATROY]

Can't we use merge to perform the SCD2 implementation?

[@ankitbansal6]

Performance is not good with merge.

[@anudipray4492]

1ST TABLE IS UPSERT NOT TRANCATE LOAD RIGHT?

[@veereshk6065]

Thank you for creating such quality content. I have a question, is it possible to implement such SCD2 using merge ? (where update and insert are involved to maintain history, same example as described in video). Thanks in advance.

[@ankitbansal6]

It can be done but merge operation can have performance issues.

[@HumansofChn]

Can't we implement it using Merge statemnet

[@techmania979]

Can’t we use merge statement instead of using two separate insert and update statements???

[@ankitbansal6]

Performance not good with merge

[@vijiinfo]

❤❤❤

[@vilasshrirame6868]

ELT and ETL approaches are different in operations

[@sowjanyamasna3313]

Sir which one is first video I learn to this course I start my career plz help me

[@ankitbansal6]

kzbin.info/www/bejne/m5vHepqPhcuWjJY

[@TheSanket148]

What if same record comes in staging table,how to handle it?@ankit

[@ankitbansal6]

That is the case of copy records. We can check if the key and value are the same then ignore them

[@prashantmhatre9225]

Not sure what you have not implemented by using merge statement

[@wizard5828]

How we can have data till last three change of id … suppose if id 1 iPhone12 40000 Changes to id 1 iphone12 30000 Changes to Id 1 iphone12 25000 Changes to id 1 iphone12 20000 I want in the final table last 3 changes only that means dont want first change that means when prize was 40000 .. this first record will be ignore give me explanation Output data 20k 25k 30k

[@nupoornawathey100]

for mysql query is slightly changed: set @updated_date='2024-01-20'; UPDATE product_type1_dim a, product_stg b SET a.price = b.price, a.last_update = @updated_date WHERE a.product_id = b.product_id ;

[@abdul-l4j]

bro keep the pace slow. You speak too fast

[@ankitbansal6]

Ok next time. You can reduce speed from settings.

[@9940114158]

Thank you Ankit