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Question: What configuration options have you used?

Answer: This is an important one. Configuration should always be dynamic and usually is done using XML

and/or Environment Variable and SQL Table with all configurations.

Question: How do you apply business rules in SSIS (Transformations.Specific calcula tions but also

cleansing)?

Answer: Some people use SSIS only to extract data and then go with stored procedures only.they are usually

missing the point of the power of SSIS. Which allows to create "a flow" and on each step applies certain rules

this greatly simplifies the ETL process and simplicity is very good.

Question: How to quickly load data into sql server table?

Answer: Fast Load option. This option is not set by default so most developers know this answer as otherwise

the load is very slow.

Question: Give example of handling data quality issues?

Answer: Data Quality is almost always a problem and SSIS handles it very well. Examples include importing

customers from different sources where customer name can be duplicates. For instance you can have as

company name: SQL Server Business Intelligence but also SQL Server BI or SQL Server BI LTD or SQL

Server BI Limited or intelligence (with one l). There are different ways to handle it. Robust and time consuming

is to create a table with or possible scenarios and update it after each update. You can also use fuzzy grouping

which is usually easy to implement and will make usually very good decisions but it is not 100% accurate so

this approach has to be justified. Other typical quality issues are nulls (missing values), outliers (dates like 2999

or types like 50000 instead of 5000 especially important if someone is adjusting the value to get bigger bonus),

incorrect addresses

and these are either corrected during ETL, ignored, re-directed for further manual updates or it fails the

packages which for big processes is usually not practised.

Question: When to use Stored Procedures?

Answer: This was one of the requested question in comment (at the bottom of the page). This one is very

important but also tricky. ALL SSIS developers have SQL Server background and that is sometime not very

good if they use SQL not SSIS approach.

Let's start with when you typically use SPs. This is for preparing tables (truncate), audit tasks (usually part of

SSIS framework), getting configuration values for loops and a few other general tasks.

During ETL extract you usually type simple SQL because it comes from other sources and usually over

complication is not a good choice (make it dynamic) because any changes usually affect the package which has

to be updated as well.

During Transformation phase (business rules, cleaning, core work) you should use Transformation tasks not

Stored procedures! There are loads of tasks that make the package much easier to develop but also a veryimportant reason is readability which is very important for other people who need to change the package and

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