Database Migration/ETL Testing

Question 1

What’s a business rule?

Answer 1

Business Rules are used every day to define entities, attributes, relationships and constraints.

Question 2

Movement of data from old database to a new database

Answer 2

What’s database migration

Question 3

Source database or legacy database

Answer 3

Old database

Question 4

Target database or destination database

Answer 4

New database

Question 5

What’s ETL

Answer 5

Extract Transform and Load

Question 6

Does the ETL tool have business rule?

Answer 6

yes it has business rule to increase data quality

Question 7

Why do we need to DB migration testing?

Answer 7

To check if all entities are migrated to the correct tables
To check if all the attributes of the entities are migrated.
To check what’s the quality of data before and after migration.

Question 8

What’s the DB migration testing approach

Answer 8

Design Validation Test:
a) We design the validation tests using SQL queries for both the source and target database
b) We put the queries in the right order
Create Test Environment
Run Database Migration Process
Run Validation Tests
Analyze and Report the Results

Question 9

Potential problems in ETL testing

Answer 9

Source data might change.
Mitigation: Back up source and target

Source data has junk values.
Mitigation: ETL tool should handle the corrupt data

Source/Target Mappings might change.
Mitigation: Write tests for unchanged mapping first and rest once they are finalized

Part of the source data is rejected.
Mitigation: Run modular validation query

Time to complete.
Mitigation: Run validation query in the ETL tool so they run automatically.