ETL Testing Interview Questions & Answers - Part 4

Advanced ETL Testing Interview Questions & Answers 

Q1. How can you create BPT test scripts?

A1. Please follow the below steps to create BPT:

First you have to go Business Components section of ALM,

1. create a new component there
2. create component steps with parameters
3. put parameter variables in bracket like <<< input1 >>>
4. check it’s reflecting in parameters
5. add details for business component
6. Make status ready once all the steps are written.

Now go to the Test Plan in ALM,

1. Create a new test script; type will be Business Process for the same.
2. Put all the required details for script
3. In test script tab, you have to pull component now which you have created (you can pull more than one component as required and integrate them in particular test script)
4. After that you can see the parameters which you defined earlier for components here (suppose you have defined 4 parameters for the component then you can see 4 i/o parameters , iteration will be default 1 )
5. If you want to check the same parameters for different iterations then you can increase the iteration here
6. Now, BPT is ready (you can see green box)

Q2. How can you run BPT test scripts?

A2. Please follow the below steps to run BPT test scripts:

First go to Test Plan in ALM,

1. Go to test script tab for BPT test scripts, click on iterations
2. Default 1 iterations is mentioned there, after clicking this, you get the parameters list
3. Define the variable value which you want to pass for all the parameters
4. If you want to add one more iteration then, click on add iteration above
5. Now you can define parameter values for added iterations as well.
6. After defining all the values, we can pull this script in test lab

Now go to Test Lab in ALM,

1. Go to the particular BPT which you want to run, click on run with manual runner
2. Now all the defined parameter values will be substituted
3. You need to follow the steps now
4. check all the iterations are checked for mentioned steps and pass it
5. BPT will be passed.

Q3. How can we link the existing defects with particular test case?

A3. Go to particular test case in Test Lab in ALM, double click on it, windows will appear. Click on Linked Defects tab, then click on Link Existing Defects then we can put defect id and click on Link. That defect will be linked with that particular test case.

Q4. Let’s suppose for making table loading faster, index will be disabled as pre-load activity, and then duplicates got loaded. Again after loading, in pos load activity index will be enabled that time it will fetch error. How to resolve this issue?

A4. You can follow the below steps to mitigate this issue –

1. First we have to disable primary constraint
2. drop the index after that
3. Remove the duplicates using rowid
4. Now create the index on the table
5. At last we can enable the primary constraint

Q5.How can we pass the variable value through command box in teradata?

A5. We can use the below query for this –

SELECT COUNT(*)

FROM <TABLE_NAME>

WHERE <date_field> = CAST('?yyyymmdd' AS DATE FORMAT 'yyyymmdd')

Q6.How can we search particular job in control M?

A6.you can follow the below steps to find out the job in control m –

1. Login to control m
2. Click customizable filter in view point tab of control m
3. Filter based on folder name and server name ( we can give wild characters here *)
4. After filtering we can see all the instances for jobs coming under that folder
5. In particular folder, all the jobs coming under that will be shown

Q7. How can we check the roles assigned to particular tables/view in teradata?

A7. We can use dbc.allrolerights table to find out the roles assigned to table/view

Select * from dbc.allrolerights where tablename= <table_name>

We can see the fields for role names, access rights, and grantor names here.

Q8. In control m, how can we run the job instantly which is in waiting due to dependencies or schedule?

A8. Do right click on that particular job, free that job and click run now.

Q9. In control m, how can we order a new job which is not scheduled?

A9.Click order button on home tab, select control m server, folder, particular job (if all jobs selected then all the jobs for particular folder will be submitted to run). Also check boxes ignore scheduling criteria and order as independent flow.

Q10. How can we modify command for particular job in control m?

A10. Do right click on particular job, go to properties, click on modify job, now we can change the commands and other things like schedule for that job.

Q11. In Tivoli, some job is stuck due to dependencies and resource constraints then how can we run that job?

A11. Right click on job stream, increase the priority to 101, release all dependencies, and remove time restrictions, then job should run. If still it’s stuck then do the same thing at job level; it will definitely run.

Q12. In Tivoli, how can we submit the jobstream which are not scheduled?

A12. Go to default database jobstream , search that particular jobstream , you can submit that jobstream from there. It will be reflected in scheduled job stream.

Note : If jobstream is in draft mode, then we can't submit that job. Jobstream should be active then only we can submit to plan. 

Data Warehouse / ETL (Extract, Transform and Load) Concepts

 

In this post, we will go through data warehouse concepts like OLAP & OLTP System, Origin of DSS System, what is data warehouse, different architecture of data warehouse systems, dimension modelling, fact and dimension tables, star and snow flake schems. I believe that the best way to learn any concept is to ask questions like 'Why this came into existence?' , 'How things are evolved for particular system?' ,'Why this can be done by this way only?' . So, guys please post the questions whatever comes in your mind while going through this topic.

OLTP (Online Transactional Processing System) / Operational System -

• OLTP systems are the systems which contain current operational data used to control and run fundamental business task . Example : ATM Machine, Airline Reservation system etc.
• They are characterized by a large number of short online transactions (INSERT, DELETE, UPDATE) .
• The main significance for OLTP systems is put on very fast processing and maintain data integrity in multi-access environment.
• Queries of OLTP systems are typically simple and return very few records.
• The structure of OLTP systems are highly normalized (usually 3NF) which means tables and fields are organized to minimize data redundancy and data dependency.
• OLTP data is very critical to run the business (data loss may lead to monetary loss or legal liability) , so backup and recovery is very important here.

OLAP (Online Analytical Processing System ) / DSS (Decision Support System) -

• OLAP systems are the systems which contain historical data used to analyse the trend, support strategic business decision and present the data on demand by customer, third party customer or legal entities .Example : MIS Systems, Airline DWH System which collects last 10 years data about flight reservation.
• They are chracterized by relatively low volume of transactions.
• In OLAP systems, there is aggregated historical data stored in multi-dimensional schemas (usually star schema) .OLAP systems are used for data mining as well.
• OLAP emphasis is on retrieval and it organizes result data of adhoc queries in reasonable amount of time.
• Queries of OLAP systems are very complex and involve aggregation of records.
• The sructure of OLAP systems are de-normalized with fewer tables which will help in faster retrieval of data using complex queries.
• OLAP system is updated by periodic process that works in stand-alone mode (consistency can be assured through update process).
• Instead of regular backup some environment may consider smply reloading OLTP data as a recovery method.

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