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Transcript of INFORMATICA FAQS
1. Assignment task in informatica 2. what is a source qualifier?It represents all data queried from the source. 3. What is a Shortcut and What is the difference between a Shortcut and a Reusable Transformation? 4. What is difference between source based commit) and target based commit? 5. what types of Errors occur when you run a session, can you describe them with real time example 6. What is key factor in BRD? 7. How to implement de-normalization concept in Informatica Mappings? 8. What is intermediate task in informatica? In what situation this task will be executed? 9. How many types of facts and what are they? 10. Performance tuning in Informatica? 11. How to append records in flat file using Informatica?For eg : In Datastage we can append the records in flat file(sequential file) using the options i) overwrite the existinf file.ii) Append the existing file. 12. How to append the records in flat file(Informatica) ? Where as in Datastage we have the options i) overwrite the existing fileii) Append existing file 13. how to get the first 100 rows from the flat file into the target? 14. Explain pmcmd? 15. Explain Session Recovery Process? 16. in which particular situation we use unconnected lookup transformation? 17. parameter file how to create parameter file and how to use it in a mapping explain with example 18. aggregator transformation how does sorted input works in aggregator transformation 19. Informatica Working with flat files how can we display delimiters beside column names of target flat file? 20.How many repositories can we create in Informatica?What is aggregate awareness? 21. How can we delete duplicate rows from your source in mapping without using SELECT DISTINCT option in source qualifier?
22. What is Target Update Override? What is the Use ? 23. When we are having data in the target table and there are no primary key or foreign key mentioned in the target table then how will you update as well as insert the data? 24. 1.how to enter same record twice in target table? give me syntax.2. how to get particular record from the table in informatica?3.how to create primary key only on odd numbers?4. how to get the records starting with particular letter like A in informatica? 25. How can you join two tables without using joiner and sql override transformations? 26. Can u start a batches with in a batch? U can not. If u want to start batch that resides in a batch,create a new independent batch and copy the necessary sessions into the new batch. 27. Can u copy the batches? 28. What is the difference between SQL Overriding in Source qualifier and Lookup transformation? 29. Informatica : set statement in update Need to update the existing records,The record which is coming for update should be inserted and also the previous record's one column must be modified. i have used look up to look up the data.used ro 30. Informatica sessions what is the difference between a session and a task? 31. What is source qualifier transformation? When U add a relational or a flat file source definition to a maping,U need to connect it to a source qualifer transformation.The source qualifier transformation represnets the records that the inform 32. What are tracing levels in transformation? 33. What are Meta Data Extenstions used in an informatica mapping? What is the significance,usage and how informatica handles them? 34. In your mapping using sequence generator transformation, the limitation of the transformation is it generates key values only around 2 million. If it is more than 3 million records are there in your source, how will you generate key values and load into target. 35. why do we need lookup sql override? Do we write sql override in lookup with special aim? 36. Informatica union transformation What is the practical use of a union transformation? 37. How many types of TASKS we have in Workflomanager? What r they?
38. What is the size of data mart? 39. Repository deletion what happens when a repository is deleted?If it is deleted for some time and if we want to delete it permanently?where is stored (address of the file) 40. Informatica objects File Format What is the file extension and format of the files for the Informatica objects like Mappings, sessions etc in the repository ? 41. how to use the shared cache feature in look up transformation 42. what are the steps follow in performance tuning ? 43. In case of use of dynamic lookup cache in a lookup transformation, the lookup cache gets updated first and then the target table. What happens if the target table rejects a row after it is updated in the Cache? 44. In which condtions we can not use joiner transformation(Limitaions of joiner transformation)? Both pipelines begin with the same original data source. Both input pipelines originate from the same Source Qualifier transformation. Both input pipelines originate from the same Normalizer transform 45. What is the use of Shared Folder? 46. What is Informatica basic data flow? 47. what is the difference between reusable transformation and mapplets? 48. What is the functionality of Lookup Transformation (connected & un connected) Asked by: M.Maheswar Reddy 49. How do you maintain Historical data and how to retrieve the historical data? 50. Which transformation replaces the look up transformation? 51. What are Dimensions and various types of Dimensions? set of level properties that describe a specific aspect of a business, used for analyzing the factual measures of one or more cubes, which use that dimension. Egs. Geography, time, customer and produc 52. What is pre-session and post-session? 53. which activities can be performed using the repository manager? 54. what is the difference between source qualifier transformation and filter transformation? 55. What r the diffrence between joiner transformation and source qualifier transformation? U can join hetrogenious data sources in joiner transformation which we can not achieve in source qualifier transformation. U need matching keys to join two relational sources in source qualifier trans
56. why do we use reusable sequencegenerator transformation only in mapplet? 57. what is the economic comparision of all the Informatica versions? 58. What is one disadvantage of using an unconnected (sometimes called function mode) Lookup transformation? (1) If there is no match in the Lookup condition, the Informatica server returns a transformation error(2) A reusable unconnected Lookup can not have more than one instance in a mapping(3) An unconnected Lookup transformation does not support user-defined default values(4) An unconnected Lookup transformation does not support a static lookup cache 59. when we create a target as flat file and source as oracle.. how can i specify first rows as column names in flat files.. 60. Eliminate Duplicate Records 61. How to assign a work flow to multiple servers? I have multiple servers, I want to assign a work flow to multiple servers Asked by: SRIRAM N 62. What are the locks with respect to mappings?How do you manually lock or unlock the mappings for chages? 63. What is the default join that source qualifier provides? Inner equi join. 64. How to read rejected data or bad data from bad file and reload it to target? 65. Discuss the advantages & Disadvantages of star & snowflake schema? 66. Can U use the maping parameters or variables created in one maping into another maping? 67. If i done any modifications for my table in back end does it reflect in informatca warehouse or maping desginer or source analyzer? NO. Informatica is not at all concern with back end data base.It displays u all the information that is to be stored in repository.If want to reflect back end changes to informatica screens, again u h 68. Suppose I have one source which is linked into 3 targets.When the workflow runs for the first time only the first target should be populated and the rest two(second and last) should not be populated.When the workflow runs for the second time only the second target should be populated and the rest two(first and last) should not be populated.When the workflow runs for the third time only the third target should be populated and the rest two(first and second) should not be populated.Could any one 69. total how many joiner transformations needed to join 10 different sources.(recent tcs intervie w question) 70. How do you migrate from one environment to another like development to production in Informatica. 71. In what all transformations the mapplets cant be used in informatica??
72. What r the mapings that we use for slowly changing dimension table? Type1: Rows containing changes to existing dimensions are updated in the target by overwriting the existing dimension. In the Type 1 Dimension mapping, all rows contain current dimension data. 74. Can we revert back reusable transformation to normal transformation? 75. inteview questionwhy do u use a reusable sequence genator tranformation in mapplets? 76. 1)how can we delete the cache files while we using aggregator transformaation? 2)exlain about cache files handling in informatica3) there are two flat files and the two flat files contain two fileds as states.both the flat files contain duplicates how to eliminate this duplicates?4) can we use lookup transformation with out using source qualifier transformation? 77. When do you use Normal Loading and the Bulk Loading, Tell the difference? 78. How do you define fact less Fact Table in Informatica 79. What is Repository size, What is its min and max size? 80. would you recommend using an orderby clause as part of a lookup sql override for a cached lookup da 81. Have you implmented Lookup in your mapping, If yes give some example? 82. What is aggregate cache in aggregator transforamtion? The aggregator stores data in the aggregate cache until it completes aggregate calculations.When u run a session that uses an aggregator transformation,the informatica server creates index and data ca 83. Wh