DATASTAGE INTERVIEW QUESTIONS

                      DATASTAGE INTERVIEW QUESTIONS

ü What does a Config File in parallel extender consist of?

ü  Types of Parallel Processing in datastage

ü  How to handle Date convertions in Datastage Convert mm/dd/yyyy format to yyyy-dd-mm?

ü  Question: What are OConv () and Iconv () functions and where are they used?

ü  How to run a Shell Script within the scope of a Data stage job?

ü  What are the command line functions that import and export the DS jobs?

ü  How do you execute datastage job from command line prompt?

ü  What is the Usage of Containers? What are its types?

ü  What are Static Hash files and Dynamic Hash files?

ü  What are types of Hashed File?

ü  What is Hash file stage and what is it used for?

ü  What is the default cache size? How do you change the cache size if

ü  What are Stage Variables, Derivations and Constants?

ü  Differentiate Primary Key and Partition Key?

ü  Orchestrate Vs Datastage Parallel Extender

ü  What is the flow of loading data into fact & dimensional tables?

ü  What is the default cache size? How do you change the cache size if needed?

ü  What are types of Hashed File?

ü  What is Modulus and Splitting in Dynamic Hashed File?

ü  What are stage variables, in dynamic hashed file?

ü  Types of views in data stage director?

ü  Types of parallel processing? 

ü  Orchestrate Vs Data stage Parallel Extender?

ü  Importance of surrogate key in data warehousing?

ü  How to run a shell script within the scope of a data stage job?

ü  How to handle date conversions in data stage? Convert an mm/dd/yyyy format to yyyy-dd-mm?

ü  Functionality of Link Partitioner and Link Collector?

ü  How do you execute datastage job from command line prompt

ü  Types of Dimensional Modeling?

ü  Differentiate Primary Key and Partition Key?

ü  Differentiate Database data and Data warehouse data?

ü  Functionality of Link Partitioner and Link Collector?

ü  What is Modulus and Splitting in Dynamic Hashed File?

ü  Types of views in Datastage Director?

ü  Did you Parameterize the job or hard-coded the values in the jobs?

ü  Have you ever involved in updating the DS versions like DS 5.X, if so tell us some the steps you have taken in doing so?

ü  How did you handle reject data?

ü  What are other Performance tunings you have done in your last project to increase the performance of slowly running jobs?

ü  Tell me one situation from your last project, where you had faced problem and How did u solve it?

ü  Tell me the environment in your last projects?

ü  Types of Stages in DS? Explain with Examples

ü  What are active stages and passive stages?

ü  Can you filter data in hashed file? (No)

ü  Difference between sequential and hashed file?

ü  How do you populate time dimension?

ü  Can we use target hashed file as lookup? (Yes)

ü  What is Merge Stage?

ü  What is Job Sequencer?

ü  What are stages in sequences?

ü  How do you pass parameters?

ü  What parameters you used in your project?

ü  What are log tables?

ü  What is job controlling?

ü  Facts and dimension tables?

ü  Confirmed dimensions?

ü  Difference between OLTP and OLAP?

ü  Difference between star schema and snow flake schema?

ü  What are hierarchies? Examples?

ü  What are materialized views?

ü  What is aggregation?

ü  What is surrogate key? Is it used for both fact and dimension tables?

ü  Why do you go for oracle sequence generator rather than datastage routine?

ü  Flow of data in datastage?

ü  Initial loading and incremental loading?

ü  What is SCD? Types?

ü  How do you develop SCD type2 in your project?

ü  How do you load dimension data and fact data? Which is first?

ü  Difference between oracle function and procedure?

ü  Difference between unique and primary key?

ü  Difference between union and union all?

ü  What is minus operator?

ü  What is audit table?

ü  If there is a large hash file and a smaller oracle table and if you are looking up from transformer in different jobs which will be faster?

ü  Tell me about SCD’s?

ü  How did you implement SCD in your project?

ü  What are derivations in transformer?

ü  How do you use surrogate key in reporting?

ü  Logs view in datastage, logs in Informatica which is clear?

ü  How does pivot stage work?

ü  What is surrogate key? What is the importance of it? How did you implement it in your project?

ü  Totally how many jobs did you developed and how many lookups did you use totally?

ü  How do constraint in transformer work?

ü  How will you declare a constraint in datastage?

ü  How will you handle rejected data?

ü  Give me some performance tips in datastage?

ü  Can we use sequential file as a lookup?

ü  How does hash file stage lookup?

ü  Why can’t we use sequential file as a lookup?

ü  What is data warehouse?

ü  What is ‘Star-Schema’?

ü  What is ‘Snowflake-Schema’?

ü  What is difference between Star-Schema and Snowflake-Schema?

ü  What is mean by surrogate key?

ü  What is ‘Conformed Dimension’?

ü  What is Factless Fact Table?

ü  When will we use connected and unconnected lookup?

ü  Which cache supports connected and unconnected lookup?

ü  What is the difference between SCD Type2 and SCD Type3?

ü  What is difference between data mart and data warehouse?

ü  What is composite key?

ü  What is surrogate key? When you will go for it?

ü  What is dimensional modeling?

ü  What are SCD and SGT? Difference between them? Example of SGT from your project.

ü  How do you import your source and targets? What are the types of sources and targets?

ü  What is Active Stages and Passive Stages means in datastage?

ü  What is difference between Informatica and DataStage? Which do you think is best?

ü  What are the stages you used in your project?

ü  What do you mean by parallel processing?

ü  What is difference between Merge Stage and Join Stage?

ü  What is difference between Copy Stage and Transformer Stage?

ü  What is difference between ODBC Stage and OCI Stage?

ü  What is difference between Lookup Stage and Join Stage?

ü  What is difference between Change Capture Stage and Difference Stage?

ü  What is difference between Hashed file and Sequential File?

ü  What are different Joins used in Join Stage?

ü  How you decide when to go for join stage and lookup stage?

ü  What is partition key? Which key is used in round robin partition?

ü  How do you handle SCD in datastage?

ü  What are Change Capture Stage and Change Apply Stages?

ü  How many streams to the transformer you can give?

ü  What is primary link and reference link?

ü  What is routine? What is before and after subroutines? These are run after/before job or stage?

ü  What is Config File? Each job having its own config file or one is needed?

ü  What is Node?

ü  What is IPC Stage? What it increase performance?

ü  What is Sequential buffer?

ü  What are Link Partioner and Link Collector?

ü  What are the performance tunning you have done in your project?

ü  Did you done scheduling? How? Can you schedule a job at the every end date of month? How?

ü  What is job sequence? Had you run any jobs?

ü  What is status view? Why you clear this? If you clear the status view what internally done?

ü  What is hashed file? What are the types of hashed file? Which you use? What is default?

ü  What is main advantage of hashed file? Difference between them. (static and dynamic)

ü  What are containers? Give example from your project.

ü  What are parameters and parameter file?

ü  How do you convert columns to rows and rows to columns in datastage? (Using Pivot Stage).

ü  What is Pivot Stage?

ü  "What is execution flow of constraints, derivations and variables in transformer stage? What are these?"

ü  How do you eliminate duplicates in datastage? Can you use hash file for it?

ü  If 1st and 8th record is duplicate then which will be skipped? Can you configure it?

ü  How do you import and export datastage jobs? What is the file extension? (See each component while importing and exporting).

ü  How do you rate yourself in DataStage?

ü  Explain DataStage Architecture?

ü  What is repository? What are the repository items?

ü  What is difference between routine and transform?

ü  When you write the routines?

ü  What is the complex situation you faced in DataStage?