How would you implement SCD Type 2 in informatica with example?
HOW TO: Implement SCD Type-2 Mapping in Informatica Cloud (IICS)
- Select the Source Object.
- Create Output Fields and Checksum Value.
- Look up on Target Object based on Natural Key.
- Flag data based on output from Lookup.
- Route data to different targets based on Flag.
- Configure Sequence Generator for generating Surrogate Keys.
How is SCD Type 2 implemented?
SCD Type 2 methodology is implemented where historical data is maintained in the Dimension table. This method doesn’t overwrites the old data in the dimension table with the new data, perhaps it keeps the previous data and new data with proper versioning using Flags or Timestamps.
How do you implement SCD Type 2 in ETL?
If you notice closely the scd2 or target table has four additional columns the surrogate key eid underscore s which is a sequence number. And is updated by one every time a new record is inserted.
How do you implement SCD Type 2 without using update strategy?
Have a sequence generator in the mapping and that is the Surrogate key and then at the session level treat all rows as insert. Make sure that there is no unique index. Because if the same values for those columns processed again the ETL will fail. You can’t treat all rows as Insert and build a Type 2 SCD.
How do you implement SCD Type 2 in Informatica without lookup?
We can use SCD without using lookup.
- Mahendra Rajpoot. Answered On : Sep 17th, 2014.
- Yes it is possible. Use left outer join query between source and target table in SQ to achieve look up functionality. Send this output to EXPR and then RTR for condition check SCD 2. Then insert and update Target based on RTR conditions.
How do you test the SCD Type 2 is implemented properly in a employee table?
Testing Type 2 Slowly Changing Dimensions using ETL Validator
- Testing SCD Type 2 Dimensions.
- Test 1: Verifying the Current Data.
- Test 2: Verifying the uniqueness of the key columns in the SCD.
- Test 3: Verifying that historical data is preserved and new records are getting created.
How do you test SCD Type 2 is implemented properly in an employee table?
Can we implement SCD Type 2 without lookup?
We can use SCD without using lookup.
Can we update records without using update strategy in Informatica?
When we configure an Informatica Power Center session, we have several options for handling database operations such as insert, update, and delete, by using these properties we can update records without using any transformations. UPDATE Categories SET CategoryName=’Cooldrinks’ WHERE CategoryID IN (3,6);
Can we use dynamic lookup in SCD Type 2?
In order to build SCD mappings, you need to check if the data is in your target. You can do that by simply reading the target as a source and using a Joiner Transformation . It’s possible to use a dynamic Lookup , but that is not really needed.
Can we use dynamic lookup in SCD 2?
This scenario where duplicates are expected in the source data can be handled using Dynamic lookup cache. The below mapping illustrates the design of SCD Type-2 implementation in Informatica Cloud Data Integration.
Can we update the target without primary key?
Your only way to update without primary key is to write an Target override in Target.By doing this, you dont need primary key for updation.
Can we use update strategy flat file?
Yes, you can use update strategy for flat filesflat filesA flat-file database is a database stored in a file called a flat file. Records follow a uniform format, and there are no structures for indexing or recognizing relationships between records. The file is simple. A flat file can be a plain text file (e.g. csv, txt or tsv), or a binary file.https://en.wikipedia.org › wiki › Flat-file_databaseFlat-file database – Wikipedia but it works only for insert, but not updates and deletes.
Can we generate surrogate keys in Informatica?
Surrogate keys are used to store history and they are generated using sequence generator . Also you can version the records using sequence no using look up and expression transformation.
How do you truncate a target table in Informatica?
Truncate table before loading data using Informatica [HowTo]
- Go to workflow manager.
- Create new session on mapping created before in designer.
- Right click session and hit edit…
- Go to mapping tab.
- Select a target from left column.
- Under properties section check “truncate target table option”
Can we update records without using update strategy?
When we configure an Informatica Power Center session, we have several options for handling database operations such as insert, update, and delete, by using these properties we can update records without using any transformations.
What is difference between primary key and surrogate key?
Surrogate key and primary key are two types of keys. The main difference between surrogate key and primary key is that surrogate key is a type of primary key that helps to identify each record uniquely, while the primary key is a set of minimal columns that helps to identify each record uniquely.
Is sorter active or passive transformation?
The Sorter transformation is a passive transformation. You can use the Sorter transformation to increase performance with other transformations. For example, you can sort data that passes through a Lookup or an Aggregator transformation configured to use sorted incoming fields.
What is truncate and load?
Truncate & Load: The target table is deleted completely first, and all data records from source system is inserted afresh. Delta Load: Here, the source data records are first checked for changes i.e. New records inserted and Old records updated. Only records that have valid changes are updated in the target.
What is meant by truncation?
1 : to shorten by or as if by cutting off. 2 : to replace (an edge or corner of a crystal) by a plane. truncate.
Can a surrogate key be duplicated?
Surrogate keys are unique.
Because surrogate keys are system-generated, it is impossible for the system to create and store a duplicate value.
Can natural key be null?
They are a special type of unique keys, with a couple of additional considerations: The column or columns that are members of a primary key cannot accept NULL values.
Can we connect 2 active transformations in Informatica?
You cannot connect multiple active transformations or an active and a passive transformation to the same downstream transformation or transformation input group. You might not be able to concatenate the rows.
Can mapplet have target?
Mapplet can have an expression transformation. The output of a mapplet cannot be connected to any target table. You cannot include the following objects in a mapplet: Normalizer transformations.
Can we rollback truncate?
You cannot ROLLBACK TRUNCATE
Simply, you cannot rollback a transaction if it is already committed but you can do something else to get the data back (or at least some parts of it). When you execute the TRUNCATE statement, your data is still in the MDF file.