21⟩ How to stop a batch?
By using server manager or pmcmd.
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128 Informatica Data Warehousing Questions And Answers
22⟩ Explain How to import oracle sequence into Informatica?
CREATE ONE PROCEDURE AND DECLARE THE SEQUENCE INSIDE THE PROCEDURE,FINALLY CALL THE PROCEDURE IN INFORMATICA WITH THE HELP OF STORED PROCEDURE TRANSFORMATION.
23⟩ What is a command that used to run a batch?
pmcmd is used to start a batch.
24⟩ If two relational tables are connected to SQ Trans, what are the possible errors it will be thrown?
The only two possibilities as of I know is
Both the table should have primary key/foreign key relation ship
Both the table should be available in the same schema or same database
25⟩ What is the difference between Informatica 7.0 and 8.0?
The basic diff b/w inbetween informatica8.0and informatica7.0 is that in 8.0series informatica corp has introduces powerexchnage
concept
26⟩ How to handle decimal places while importing a flatfile into informatica?
while importing flat file definetion just specify the scale for a neumaric data type. in the mapping, the flat file source supports only number datatype(no decimal and integer). In the SQ associated with that source will have a data type as decimal for that number port of the source.
source ->number datatype port ->SQ -> decimal datatype.Integer is not supported. hence decimal is taken care.
Import the field as string and then use expression to convert it, so that we can avoid truncation if decimal places inj source itself.
27⟩ Explain How to get the first 100 rows from the flat file into the target?
1. Use test download option if you want to use it for testing.
2. Put counter/sequence generator in mapping and perform it.
Its simple.take a filter drag all ports from source qualifier to filter. in filter write the condition columname<101 and drag ports to the target
28⟩ Explain the Differences between Normalizer and Normalizer transformation?
Normalizer: It is a transormation mainly using for cobol sources,
it's change the rows into coloums and columns into rows
Normalization:To remove the retundancy and inconsitecy
Normalizer Transformation can be used to obtain multiple columns from a single row.
29⟩ Explain What are the measure objects?
Aggregate calculation like sum,avg,max,min these are the measure objetcs.
30⟩ Explain What are the basic needs to join two sources in a source qualifier?
Two sources should have primary and Foreign key relation ships.
Two sources should have matching data types.
Basic need to join two sources using source qualifier:
1) Both sources should be in same database
2) The should have at least one column in common with same data types
31⟩ How to load time dimension?
We can use SCD Type 1/2/3 to load any Dimensions based on the requirement.
We can also use procedure to populate Time Dimension
32⟩ What is the use of incremental aggregation? Explain me in brief with an example?
Its a session option. when the informatica server performs incremental aggr. it passes new source data through the mapping and uses historical chache data to perform new aggregation caluculations incrementaly. for performance we will use it.
When using incremental aggregation, you apply captured changes in the source to aggregate calculations in a session. If the source changes incrementally and you can capture changes, you can configure the session to process those changes. This allows the Integration Service to update the target incrementally, rather than forcing it to process the entire source and recalculate the same data each time you run the session.
For example, you might have a session using a source that receives new data every day. You can capture those incremental changes because you have added a filter condition to the mapping that removes pre-existing data from the flow of data. You then enable incremental aggregation.
When the session runs with incremental aggregation enabled for the first time on March 1, you use the entire source. This allows the Integration Service to read and store the necessary aggregate data. On March 2, when you run the session again, you filter out all the records except those time-stamped March 2. The Integration Service then processes the new data and updates the target accordingly.
Consider using incremental aggregation in the following circumstances:
You can capture new source data. Use incremental aggregation when you can capture new source data each time you run the session. Use a Stored Procedure or Filter transformation to process new data.
Incremental changes do not significantly change the target. Use incremental aggregation when the changes do not significantly change the target. If processing the incrementally changed source alters more than half the existing target, the session may not benefit from using incremental aggregation. In this case, drop the table and recreate the target with complete source data.
Note: Do not use incremental aggregation if the mapping contains percentile or median functions. The Integration Service uses system memory to process these functions in addition to the cache memory you configure in the session properties. As a result, the Integration Service does not store incremental aggregation values for percentile and median functions in disk caches.
33⟩ What are the joiner caches?
Specifies the directory used to cache master records and the index to these records. By default, the cached files are created in a directory specified by the server variable $PMCacheDir. If you override the directory, make sure the directory exists and contains enough disk space for the cache files. The directory can be a mapped or mounted drive.
There r 2-types of cache in the joiner
1. Data cache
2. Index Cache
34⟩ Explain What is power center repository?
Standalone repository. A repository that functions individually, unrelated and unconnected to other repositories.
Global repository. (PowerCenter only.) The centralized repository in a domain, a group of connected repositories. Each domain can contain one global repository. The global repository can contain common objects to be shared throughout the domain through global shortcuts.
Local repository. (PowerCenter only.) A repository within a domain that is not the global repository. Each local repository in the domain can connect to the global repository and use objects in its shared folders.
Power Center repository is used to store informatica's meta data .
Information such as mapping name,location,target definitions,source definitions,transformation and flow is stored as meta data in the repository.
35⟩ Explain What is metadata reporter?
It is a web based application that enables you to run reports againist repository metadata.
With a meta data reporter,You can access information about U?r repository with out having knowledge of sql,transformation language or underlying tables in the repository.
36⟩ What are the unsupported repository objects for a mapplet?
Source definitions. Definitions of database objects (tables, views, synonyms) or files that provide source data.
Target definitions. Definitions of database objects or files that contain the target data.
Multi-dimensional metadata. Target definitions that are configured as cubes and dimensions.
Mappings. A set of source and target definitions along with transformations containing business logic that you build into the transformation. These are the instructions that the Informatica Server uses to transform and move data.
Reusable transformations. Transformations that you can use in multiple mappings.
Mapplets. A set of transformations that you can use in multiple mappings.
Sessions and workflows. Sessions and workflows store information about how and when the Informatica Server moves data. A workflow is a set of instructions that describes how and when to run tasks related to extracting, transforming, and loading data. A session is a type of task that you can put in a workflow. Each session corresponds to a single mapping.
37⟩ What is a time dimension? give an example?
In a relational data model, for normalization purposes, year lookup, quarter lookup, month lookup, and week lookups are not merged as a single table. In a dimensional data modeling(star schema), these tables would be merged as a single table called TIME DIMENSION for performance and slicing data.
This dimensions helps to find the sales done on date, weekly, monthly and yearly basis. We can have a trend analysis by comparing this year sales with the previous year or this week sales with the previous week.
38⟩ How can we transform row to column?
Through Normalizer Transformation we can do this.
39⟩ Explain Why dimenstion tables are denormalized in nature?
Because in Data warehousing historical data should be maintained, to maintain historical data means suppose one employee details like where previously he worked, and now where he is working, all details should be maintain in one table, if u maintain primary key it won't allow the duplicate records with same employee id. so to maintain historical data we are all going for concept data warehousing by using surrogate keys we can achieve the historical data(using oracle sequence for critical column).
so all the dimensions are marinating historical data, they are de normalized, because of duplicate entry means not exactly duplicate record with same employee number another record is maintaining in the table.
40⟩ How to load the data from people soft hrm to people soft erm using informatica?
Following are necessary
1.Power Connect license
2.Import the source and target from people soft using ODBC connections
3.Define connection under "Application Connection Browser" for the people soft source/target in workflow manager. select the proper connection (people soft with oracle,sybase,db2 and informix) and execute like a normal session.
