top datastage interview questions and answers job interview tips
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DESCRIPTIONYou'll likely be asked difficult questions during the interview. Preparing the list of likely questions in advance will help you easily transition from question to question.
- 1. Top 10 datastage interview questionsand answersIf you need top 7 free ebooks below for your job interview, please visit:4career.net Free ebook: 75 interview questions and answers Top 12 secrets to win every job interviews 13 types of interview quesitons and how to face them Top 8 interview thank you letter samples Top 7 cover letter samples Top 8 resume samples Top 15 ways to search new jobsInterview questions and answers free pdf download Page 1 of 30
2. Tell me about yourself?This is probably the most askedquestion in datastage interview. Itbreaks the ice and gets you to talkabout something you should be fairlycomfortable with. Have somethingprepared that doesn't sound rehearsed.It's not about you telling your life storyand quite frankly, the interviewer justisn't interested. Unless asked to do so,stick to your education, career andcurrent situation. Work through itchronologically from the furthest backto the present.Interview questions and answers free pdf download Page 2 of 30 3. Define Data Stage?A data stage is basically a tool that isused to design, develop and executevarious applications to fill multipletables in data warehouse or data marts.It is a program for Windows serversthat extracts data from databases andchange them into data warehouses. Ithas become an essential part of IBMWebSphere Data Integration suite.Interview questions and answers free pdf download Page 3 of 30 4. What Can You Do for Us That Other CandidatesCan't?What makes you unique? Thiswill take an assessment ofyour experiences, skills andtraits. Summarize concisely:"I have a unique combinationof strong technical skills, andthe ability to build strongcustomer relationships. Thisallows me to use myknowledge and break downinformation to be more user-friendly."Interview questions and answers free pdf download Page 4 of 30 5. Differentiate between datastage andinformatica?DatastageIn datastage, there is a concept ofpartition, parallelism for nodeconfiguration. While, there is noconcept of partition and parallelism ininformatica for node configuration.Also, Informatica is more scalable thanDatastage. Datastage is more user-friendlyas compared to Informatica.Interview questions and answers free pdf download Page 5 of 30 6. What steps should be taken to improveDatastage jobs?In order to improve performance ofDatastage jobs, we have to firstestablish the baselines. Secondly, weshould not use only one flow forperformance testing. Thirdly, weshould work in increment. Then, weshould evaluate data skews. Then weshould isolate and solve theproblems, one by one. After that, weshould distribute the file systems toremove bottlenecks, if any. Also, weshould not include RDBMS in startof testing phase. Last but not theleast, we should understand andassess the available tuning knobs.Interview questions and answers free pdf download Page 6 of 30 7. What is a merge?Differentiate between Join,Merge and Lookup stage?Merge is a stage that is available in bothparallel and server jobs.The merge stage is used to join twotables(server/parallel) or twotables/datasets(parallel).Merge requires that the master table/datasetand the update table/dataset to be sorted.Merge is performed on a key field, and thekey field is mandatory in the master andupdate dataset/table.All the three concepts are different from eachother in the way they use the memorystorage, compare input requirements and howthey treat various records. Join and Mergeneeds less memory as compared to theLookup stage.Interview questions and answers free pdf download Page 7 of 30 8. Differentiate between SymmetricMultiprocessing and Massive ParallelProcessing?In Symmetric Multiprocessing, thehardware resources are shared byprocessor. The processor has oneoperating system and it communicatesthrough shared memory. While inMassive Parallel processing, theprocessor access the hardwareresources exclusively. This type ofprocessing is also known as SharedNothing, since nothing is shared inthis. It is faster than the SymmetricMultiprocessing.Interview questions and answers free pdf download Page 8 of 30 9. Whats difference betweeen operational datastage (ODS) and data warehouse?A dataware house is a decision supportdatabase for organisational needs.It issubject oriented,nonvolatile,integrated ,time varient collectof data.ODS(Operational Data Source) is aintegrated collection of relatedinformation . it contains maximum 90days information.ODS is nothing but operational datastore is the part of transactionaldatabase. this db keeps integrated datafrom different tdb and allow commonoperations across organisation. eg:banking transaction.In simple terms ODS is dynamic data.Interview questions and answers free pdf download Page 9 of 30 10. How the IPC Stage work?If we used the IPC Stage betweensource and target .One process willhandling the communication fromsequential file stage to IPC stage, andother will handling communicationfrom IPC stage to ODBC stage. Assoon as the Sequential File stage hasopened its output link, the IPC stagecan start passing data to the ODBCstage.Interview questions and answers free pdf download Page 10 of 30 11. What is DataStage?Design jobs for Extraction,Transformation and Loading(ETL).Ideal tool data integration projects suchas data warehouses, data marts andsystem migrations.Import,export,create and managedmetadata for use within jobs.Schedule, run and monitor jobs allwithin DataStageAdminsters your Datastage developmentand execution environments.Interview questions and answers free pdf download Page 11 of 30 12. How many types of hash files are there?There are two types of hash files inDataStage i.e. Static Hash File andDynamic Hash File. The static hash file isused when limited amount of data is to beloaded in the target database. The dynamichash file is used when we dont know theamount of data from the source file.Interview questions and answers free pdf download Page 12 of 30 13. Differentiate between Hash file and Sequentialfile?The only difference between theHash file and Sequential file isthat the Hash file saves data onhash algorithm and on a hash keyvalue, while sequential filedoesnt have any key value tosave the data. Basis on this hashkey feature, searching in Hash fileis faster than in sequential file.Interview questions and answers free pdf download Page 13 of 30 14. Define OConv () and IConv () functions inDatastage?In Datastage, OConv () and IConv()functions are used to convert formats fromone format to another i.e. conversions ofroman numbers, time, date, radix, numeralASCII etc. IConv () is basically used toconvert formats for system to understand.While, OConv () is used to convert formatsfor users to understand.Interview questions and answers free pdf download Page 14 of 30 15. Name the different types of Lookups in Datastage?There are two types of Lookups in Datastagei.e. Normal lkp and Sparse lkp. In Normal lkp,the data is saved in the memory first and thenthe lookup is performed. In Sparse lkp, thedata is directly saved in the database.Therefore, the Sparse lkp is faster than theNormal lkp.Interview questions and answers free pdf download Page 15 of 30 16. Define Routines and their types?Routines are basically collection offunctions that is defined by DSmanager. It can be called viatransformer stage. There are three typesof routines such as, parallel routines,main frame routines and serverroutines.Interview questions and answers free pdf download Page 16 of 30 17. What is the difference between Server Job andParallel Jobs?Server Jobs works in sequential waywhile parallel jobs work in parallelfashion (Parallel Extender work on theprincipal of pipeline and partition) forInpur/Output processingInterview questions and answers free pdf download Page 17 of 30 18. Why do we use Link Partitioner and LinkCollector in Datastage?In Datastage, Link Partitioner is used todivide data into different parts throughcertain partitioning methods. LinkCollector is used to gather data fromvarious partitions/segments to a singledata and save it in the target table.Interview questions and answers free pdf download Page 18 of 30 19. How rejected rows are managed in Datastage?In the Datastage, the rejected rowsare managed through constraints intransformer. We can either placethe rejected rows in the propertiesof a transformer or we can create atemporary storage for rejected rowswith the help of REJECTEDcommandInterview questions and answers free pdf download Page 19 of 30 20. Differentiate between validated and Compiled inthe Datastage?In Datastage, validating a job means,executing a job. While validating, theDatastage engine verifies whether allthe required properties are provided ornot. In other case, while compiling ajob, the Datastage engine verifies thatwhether all the given properties arevalid or not.Interview questions and answers free pdf download Page 20 of 30 21. What are Sequencers?A sequencer allows you to synchronizethe control flow of multiple activities ina job sequence. It can have multipleinput triggers as well as multiple outputtriggers.Interview questions and answers free pdf download Page 21 of 30 22. Useful job interview materials:If you need top free ebooks below for your job interview, please visit:4career.net Free ebook: 75 interview questions and answers Top 12 secrets to win every job interviews Top 36 situational interview questions 440 behavioral interview questions 95 management interview questions and answers 30 phone interview questions Top 8 interview thank you letter samples 290 competency based interview questions 45 internship interview questions Top 7 cover letter samples Top 8 resume samples Top 15 ways to search new jobsInterview questions and answers free pdf download Page 22 of 30 23. Top 6 tips for job interviewInterview questions and answers free pdf download Page 23 of 30 24. Tip 1: Do your homeworkYou'll likely be asked difficult questio