Question 1.While importing the relational source definition from database, what are the meta data of source you import?
Answer 1.
· Source name
· Database location
· Column names
· Data types
· Key constraints
Question 2. How many ways you can update a relational source definition and what are those way?
Answer 2.
Two ways
1. Edit the definition
2. Reimport the definition
Question 3.Where should you place the flat file to import the flat file definition to the designer?
Answer 3.Place it in local folder.
Question 4. To provide support for Mainframes source data, which files are used as a source definitions?
Answer 4. COBOL files
Question 5. Which transformation should you need while using the Cobol sources as source definitions?
Answer 5.Normalizer transformation which is used to normalize the data. Since COBOL sources are often consists of Demnormalized data.
Question 6. How can you create or import flat file definition in to the warehouse designer?
Answer 6. You can not create or import flat file definition in to warehouse designer directly. Instead of that you must analyze the file in source analyzer and then drag it into the warehouse designer. When you drag the flat file source definition into warehouse designer workspace, the warehouse designer creates a relational target definition not a file definition. If you want to load to a file, configure the session to write to a flat file. When the informatica server runs the session, it creates and loads the flat file.
Question 7. What is the mapplet?
Answer 7. Mapplet is a set of transformations that you build in the mapplet designer and you can use in multiple mappings.
Question 8. What is a transformation?
Answer 8. It is a repository object that generates, modifies or passes data.
Question 9. What are the designer tools for creating transformations?
Answer 9.
1. Mapping designer
2. Transformation developer
3. Mapplet designer
Question 10. What is active and passive transformation?
Answer 10. An active transformation can change the number of rows that pass through it. Passive transformation does not change the number of rows that pass through it.
Question 11. What are the connected or unconnected transformations?
Answer 11. An unconnected transformation is not connected to other transformations in the mapping.
Connected transformation is connected to other transformations in the mapping.
Question 12. How many ways you create ports?
Answer 12.
Two ways
1. Drag the port from another transformation
2. Click the add button on the ports tab.
Question 14. What are the reusable transformations?
Answer 14. Reusable transformations can be used in multiple mappings. When you need to incorporate this transformation into maping, you add an instance of it to maping.Later if you change the definition of the transformation, all instances of it inherit the changes. Since the instance of reusable transformation is a pointer to that transforamtion, you can change the transformation in the transformation developer, its instances automatically reflect these changes.This feature can save you great deal of work.
Question 15. What are the methods for creating reusable transformations?
Answer 15.
Two methods
1. Design it in the transformation developer.
2. Promote a standard transformation from the mapping designer.
After you add a transformation to the mapping, you can promote it to the status of reusable transformation. Once you promote a standard transformation to reusable status, you can demote it to a standard transformation at any time. If you change the properties of a reusable transformation in mapping, you can revert it to the original reusable transformation properties by clicking the revert button.
Questions 16.What are the unsupported repository objects for a mapplet?
Answer 16.
1. COBOL source definition
2. Joiner transformations
3. Normalizer transformations
4. Non reusable sequence generator transformations.
5. Pre or post session stored procedures
6. Target definitions
7. Power mart 3.5 styles Look Up functions
8. XML source definitions
9. IBM MQ source definitions
Question 17. What are the mapping parameters and mapping variables?
Answer 17. Mapping parameter represents a constant value that you can define before running a session. A mapping parameter retains the same value throughout the entire session. When you use the mapping parameter, you declare and use the parameter in a mapping or mapplet.Then define the value of parameter in a parameter file for the session. Unlike a mapping parameter, a mapping variable represents a value that can change throughout the session. The informatica server saves the value of mapping variable to the repository at the end of session run and uses that value next time you run the session.
Question 18. Can you use the mapping parameters or variables created in one mapping into another mapping?
Answer 18. NO. We can use mapping parameters or variables in any transformation of the same mapping or mapplet in which you have created mapping parameters or variables.
Question 19. Can you use the mapping parameters or variables created in one mapping into any other reusable transformation?
Answer 19. Yes. Because reusable transformation is not contained with any mapplet or mapping.
Question 20.How can you improve session performance in aggregator tansformation?
Answer 20. Use sorted input.
Question 21. What is aggregate cache in aggregator transformation?
Answer 21. The aggregator stores data in the aggregate cache until it completes aggregate calculations. When you run a session that uses an aggregator transformation, the informatica server creates index and data caches in memory to process the transformation. If the informatica server requires more space, it stores overflow values in cache files.
Questions 22. What are the difference between joiner transformation and source qualifier transformation?
Answer 22. You can join heterogeneous data sources in joiner transformation which we can not achieve in source qualifier transformation. You need matching keys to join two relational sources in source qualifier transformation. Where as you doesn’t need matching keys to join two sources. Two relational sources should come from same data source in source qualifier. You can join relational sources which r coming from different sources also.
Question 23. In which conditions we can not use joiner transformation (Limitations of joiner transformation)?
Answer 23. 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 transformation. Both input pipelines originate from the same Joiner transformation. Either input pipelines contains an Update Strategy transformation. Either input pipelines contains a connected or unconnected Sequence Generator transformation.
Question 24. What are the settings that you use to configure the joiner transformation?
Answer 24. Master and detail source Type of join. Condition of the join.
Question 25. What are the join types in joiner transformation?
Answer 25.
1. Normal (Default)
2. Master outer
3. Detail outer
4. Full outer
Question 26. What are the joiner caches?
Answer 26. When a Joiner transformation occurs in a session, the Informatica Server reads all the records from the master source and builds index and data caches based on the master rows. After building the caches, the Joiner transformations reads records from the detail source and perform joins.
Question 27. What is the look up transformation?
Answer 27. Use lookup transformation in your mapping to lookup data in a relational table, view, and synonym. Informatica server queries the look up table based on the lookup ports in the transformation. It compares the lookup transformation port values to lookup table column values based on the look up condition.
Question 28.Why use the lookup transformation?
Answer 28. To perform the following tasks. Get a related value. For example, if your source table includes employee ID, but you want to include the employee name in your target table to make your summary data easier to read. Perform a calculation. Many normalized tables include values used in a calculation, such as gross sales per invoice or sales tax, but not the calculated value (such as net sales). Update slowly changing dimension tables. You can use a Lookup transformation to determine whether records already exist in the target.
Questions 29.What are the types of lookup?
Answer 29. Connected and unconnected.
Question 30.What is meant by lookup caches?
Answer 30. The informatica server builds a cache in memory when it processes the first row of a data in a cached look up transformation. It allocates memory for the cache based on the amount you configure in the transformation or session properties. The informatica server stores condition values in the index cache and output values in the data cache.
Question 31. What are the types of lookup caches?
Answer 31.
Persistent cache: you can save the lookup cache files and reuse them the next time the informatica server processes a lookup transformation configured to use the cache.
Recache from database: If the persistent cache is not synchronized with he lookup table, you can configure the lookup transformation to rebuild the lookup cache.
Static cache: you can configure a static or read only cache for only lookup table. By default informatica server creates a static cache. It caches the lookup table and lookup values in the cache for each row that comes into the transformation. When the lookup condition is true, the informatica server does not update the cache while it processes the lookup transformation.
Dynamic cache: If you want to cache the target table and insert new rows into cache and the target, you can create a look up transformation to use dynamic cache. The informatica server dynamically inserts data to the target table.
Shared cache: you can share the lookup cache between multiple transactions can share unnamed cache between transformations in the same mapping.
Question 32. Difference between static cache and dynamic cache.
Answer 32.
Static cache: you can not insert or update the cache.
The informatica server returns a value from condition when the condition is false. This indicates that is true. When the condition is not true, informatica server returns the default value
Dynamic cache: You can insert rows into the cache as you pass to the target.
The informatica server inserts rows into cache when the condition is false. This indicates the row is not in the cache or target.
You can pass these rows to the target table. For connected transformations and null for unconnected transformations.
Question 33.Which transformation should we use to normalize the COBOL and relational sources?
Answer 33. Normalizer Transformation.
When you drag the COBOL source in to the mapping Designer workspace, the normalizer transformation automatically appears, creating input and output ports for every column in the source.
Question 34.How the informatica server sorts the string values in Rank transformation?
Answer 34.When the informatica server runs in the ASCII data movement mode it sorts session data using Binary sort order. If you configure the session to use a binary sort order, the informatica server calculates the binary value of each string and returns the specified number of rows with the highest binary values for the string.
Questions 35.What are the rank caches?
Answer 35. During the session, the informatica server compares an input row with rows in the data cache. If the input row out-ranks a stored row, the informatica server replaces the stored row with the input row. The informatica server stores group information in an index cache and row data in a data cache.
Question 36. What is the Rank index in Rank transformation?
Answer 36. The Designer automatically creates a RANKINDEX port for each Rank transformation. The Informatica Server uses the Rank Index port to store the ranking position for each record in a group. For example, if you create a Rank transformation that ranks the top 5 salespersons for each quarter, the rank index numbers the salespeople from 1 to 5.
Question 37.What is the Router transformation?
Answer 37. A Router transformation is similar to a Filter transformation because both transformations allow you to use a condition to test data. However, a Filter transformation tests data for one condition and drops the rows of data that do not meet the condition. A Router transformation tests data for one or more conditions and gives you the option to route rows of data that do not meet any of the conditions to a default output group. If you need to test the same input data based on multiple conditions, use a Router Transformation in a mapping instead of creating multiple Filter transformations to perform the same task.
Questions 38.What are the types of groups in Router transformation?
Answer 38.
Input group
Output group
The designer copies property information from the input ports of the input group to create a set of output ports for each output group.
Two types of output groups
User defined groups
Default group
you can not modify or delete default groups.
Question 39. Why we use stored procedure transformation?
Answer 39. For populating and maintaining data bases.
Question 40. Explain about perform recovery?
Answer 40. When the Informatica Server starts a recovery session, it reads the OPB_SRVR_RECOVERY table and notes the row ID of the last row committed to the target database. The Informatica Server then reads all sources again and starts processing from the next row ID. For example, if the Informatica Server commits 10,000 rows before the session fails, when you run recovery, the Informatica Server bypass the rows up to 10,000 and starts loading with row 10,001. By default, Perform Recovery is disabled in the Informatica Server setup. You must enable Recovery in the Informatica Server setup before you run a session so the Informatica Server can create and/or write entries in the OPB_SRVR_RECOVERY table.
Question 42.What r the types of data that passes between informatica server and stored procedure?
Answer 42.
3 types of data
· Input/Out put parameters
· Return Values
· Status code.
Question 43.What is the status code?
Answer 43. Status code provides error handling for the informatica server during the session. The stored procedure issues a status code that notifies whether or not stored procedure completed sucessfully.This value can not seen by the user. It only used by the informatica server to determine whether to continue running the session or stop.
Question 44. What is source qualifier transformation?
Answer 44. When you add a relational or a flat file source definition to a mapping, you need to connect it to a source qualifier transformation. The source qualifier transformation represents the records that the informatica server reads when it runs a session.
Question 45.What are the tasks that source qualifier performs?
Answer 45. Join data originating from same source data base. Filter records when the informatica server reads source data. Specify an outer join rather than the default inner join specify sorted records. Select only distinct values from the source. Creating custom query to issue a special SELECT statement for the informatica server to read source data.
Question 46. What is the target load order?
Answer 46. Specify the target load order based on source qualifiers in a mapping. If you have the multiple source qualifiers connected to the multiple targets you can designate the order in which informatica server loads data into the targets.
Question 47. What is the default join that source qualifier provides?
Answer 47. Inner equi join.
Question 48. What are the basic needs to join two sources in a source qualifier?
Answer 48. Two sources should have primary and foreign key relation ships.
Two sources should have matching data types.
Question 49.what is update strategy transformation?
Answer 49. This transformation is used to maintain the history data or just most recent changes in to target table.
Question 50.Describe two levels in which update strategy transformation sets?
Answer 50. Within a session. When you configure a session, you can instruct the Informatica Server to either treat all records in the same way (for example, treat all records as inserts), or use instructions coded into the session mapping to flag records for different database operations. Within a mapping. Within a mapping, you use the Update Strategy transformation to flag records for insert, delete, update, or reject.
Question 51.What is the default source option for update strategy transformation?
Answer 51. Data driven.
Question 52. What is Data driven?
Answer 52. The Informatica server follows instructions coded into update strategy transformations with in the session mapping determine how to flag records for insert,update,,delete or reject .If you do not choose data driven option setting, the Informatica server ignores all update strategy transformations in the mapping.
Questions 53.What are the options in the target session of update strategy transformations?
Answer 53.
Insert
Delete
Update
Update as update
Update as insert
Update else insert
Truncate table
Question 54. What are the types of mapping wizards that r to be provided in Informatica?
Answer 54. The Designer provides two mapping wizards to help you create mappings quickly and easily. Both wizards are designed to create mappings for loading and maintaining star schemas, a series of dimensions related to a central fact table. Getting Started Wizard. Creates mappings to load static fact and dimension tables, as well as slowly growing dimension tables. Slowly Changing Dimensions Wizard. Creates mappings to load slowly changing dimension tables based on the amount of historical dimension data you want to keep and the method you choose to handle historical dimension data.
Question 55. What are the types of mapping in Getting Started Wizard?
Answer 55.
Simple Pass through mapping: Loads a static fact or dimension table by inserting all rows. Use this mapping when you want to drop all existing data from your table before loading new data. Slowly Growing target: Loads a slowly growing fact or dimension table by inserting new rows. Use this mapping to load new data when existing data does not require updates.
Question 56. What are the mappings that we use for slowly changing dimension table?
Answer 56.
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. Use the Type 1 Dimension mapping to update a slowly changing dimension table when you do not need to keep any previous versions of dimensions in the table.
Type 2: The Type 2 Dimension Data mapping inserts both new and changed dimensions into the target. Changes are tracked in the target table by versioning the primary key and creating a version number for each dimension in the table. Use the Type 2 Dimension/Version Data mapping to update a slowly changing dimension table when you want to keep a full history of dimension data in the table. Version numbers and versioned primary keys track the order of changes to each dimension.
Type 3: The Type 3 Dimension mapping filters source rows based on user-defined comparisons and inserts only those found to be new dimensions to the target. Rows containing changes to existing dimensions are updated in the target. When updating an existing dimension, the Informatica Server saves existing data in different columns of the same row and replaces the existing data with the updates
Question 57.What is the different types of Type2 dimension mappings?
Answer 57.
Type2 Dimension/Version Data Mapping: In this mapping the updated dimension in the source will gets inserted in target along with a new version number. And newly added dimension in source will inserted into target with a primary key.
Type2 Dimension/Flag current Mapping: This mapping is also used for slowly changing dimensions. In addition it creates a flag value for changed or new dimension. Flag indicates the dimension is new or newly updated. Recent dimensions will gets saved with current flag value 1. And updated dimensions r saved with the value 0.
Type2 Dimension/Effective Date Range Mapping: This is also one flavor of Type2 mapping used for slowly changing dimensions. This mapping also inserts both new and changed dimensions in to the target. And changes r tracked by the effective date range for each version of each dimension.
Question 58.How can you recognize whether or not the newly added rows in the source are get inserted in the target?
Answer 58. In the Type2 mapping we have three options to recognize the newly added rows 1. Version number
2. Flag value
3. Effective date Range
Question 59. What are two types of processes that Informatica runs the session?
Answer 59. Load manager Process: Starts the session, creates the DTM process, and sends post-session email when the session completes. The DTM process. Creates threads to initialize the session, read, write, and transform data, and handle pre and post-session operations.
Question 60. Explain about Recovering sessions?
Answer 60. If you stop a session or if an error causes a session to stop, refer to the session and error logs to determine the cause of failure. Correct the errors, and then complete the session. The method you use to complete the session depends on the properties of the mapping, session, and Informatica Server configuration. Use one of the following methods to complete the session:
Run the session again if the Informatica Server has not issued a commit.
Truncate the target tables and run the session again if the session is not recoverable.
Consider performing recovery if the Informatica Server has issued at least one commit.
Question 61. Can you generate reports in Informatica?
Answer 61. Yes. By using Metadata reporter we can generate reports in Informatica.
Question 62.What is metadata reporter?
Answer 62.It is a web based application that enables you to run reports against repository metadata. With a Meta data reporter you can access information about your repository with out having knowledge of sql, transformation language or underlying tables in the repository.
Question 63.Define mapping and sessions?
Answer 63. Mapping: It is a set of source and target definitions linked by transformation objects that define the rules for transformation.
Session: It is a set of instructions that describe how and when to move data from source to targets.
Question 64.Which tool U use to create and manage sessions and batches and to monitor and stop the Informatica server?
Answer 64.Informatica server manager.
Question 65.Why we use partitioning the session in Informatica?
Answer 65.Partitioning achieves the session performance by reducing the time period of reading the source and loading the data into target.
Questions 66.To achieve the session partition what are the necessary tasks you have to do?
Answer 66.
Configure the session to partition source data.
Install the Informatica server on a machine with multiple CPU’s.
Question 67.How the Informatica server increases the session performance through partitioning the source?
Answer 67. For relational sources Informatica server creates multiple connections for each partition of a single source and extracts separate range of data for each connection.Informatica server reads multiple partitions of a single source concurently.Similarly for loading also Informatica server creates multiple connections to the target and loads partitions of data concurrently. For XML and file sources, informatica server reads multiple files concurently.For loading the data Informatica server creates a separate file for each partition(of a source file).you can choose to merge the targets.
Question 68. Why u use repository connectivity?
Answer 68.When you edit, schedule the session each time, informatica server directly communicates the repository to check whether or not the session and users are valid. All the metadata of sessions and mappings will be stored in repository.
Questions 69.What are the tasks that Load manger process will do?
Answer 69.Manages the session and batch scheduling: When you start the Informatica server the load manager launches and queries the repository for a list of sessions configured to run on the Informatica server. When you configure the session the load manager maintains list of list of sessions and session start times. When you start a session load manger fetches the session information from the repository to perform the validations and verifications prior to starting DTM process.
Locking and reading the session: When the Informatica server starts a session load manager locks the session from the repository. Locking prevents you starting the session again and again. Reading the parameter file: If the session uses a parameter files, load manager reads the parameter file and verifies that the session level parameters are declared in the file. Verifies permission and privileges: When the session starts load manger checks whether or not the user have privileges to run the session. Creating log files: Load manger creates log file contains the status of session.
Question 70. What is DTM process?
Answer 70. After the load manger performs validations for session, it creates the DTM process. TM is to create and manage the threads that carry out the session tasks. It creates the master thread. Master thread creates and manages all the other threads.
Question 71. What are the different threads in DTM process?
Answer 71.
Master thread: Creates and manages all other threads
Mapping thread: One mapping thread will be creates for each session. Fetches session and mapping information.
Pre and post session threads: This will be created to perform pre and post session operations.
Reader thread: One thread will be created for each partition of a source. It reads data from source.
Writer thread: It will be created to load data to the target.
Transformation thread: It will be created to transform data.
Questions 72.What are the data movement modes in Informatica?
Answer 72. Data movement modes determines how Informatica server handles the character data you choose the data movement in the Informatica server configuration settings.
Two types of data movement modes available in Informatica.
1. ASCII mode
2. Uni code mode.
Question 73. What are the output files that the Informatica server creates during the session running?
Answer 73. Informatica server log: Informatica server (on UNIX) creates a log for all status and error messages (default name: pm.server.log).It also creates an error log for error messages. These files will be created in Informatica home directory. Session log file: Informatica server creates session log file for each session. It writes information about session into log files such as initialization process, creation of sql commands for reader and writer threads, errors encountered and load summary. The amount of detail in session log file depends on the tracing level that u set. Session detail file: This file contains load statistics for each target in mapping. Session detail includes information such as table name, number of rows written or rejected. you can view this file by double clicking on the session in monitor window Performance detail file: This file contains information known as session performance details which helps you where performance can be improved. To generate this file select the performance detail option in the session property sheet. Reject file: This file contains the rows of data that the writer does not write to targets. Control file: Informatica server creates control file and a target file when U run a session that uses the external loader. The control file contains the information about the target flat file such as data format and loading instructions for the external loader. Post session email: Post session email allows U to automatically communicate information about a session run to designated recipients’. You can create two different messages. One if the session completed successfully the other if the session fails. Indicator file: If u use the flat file as a target, you can configure the Informatica server to create indicator file. For each target row, the indicator file contains a number to indicate whether the row was marked for insert, update, delete or reject. Output file: If session writes to a target file, the Informatica server creates the target file based on file properties entered in the session property sheet. Cache files: When the Informatica server creates memory cache it also creates cache files. For the following circumstances Informatica server creates index and data cache files. Aggregator transformation Joiner transformation Rank transformation Lookup transformation.
Question 74.In which circumstances that Informatica server creates Reject files?
Answer 74.
When it encounters the DD_Reject in update strategy transformation.
Violates database constraint
Filed in the rows was truncated or overflowed.
Question 75. What is polling?
Answer 75. It displays the updated information about the session in the monitor window. The monitor window displays the status of each session when U poll the Informatica server.
Question 76. Can you copy the session to a different folder or repository?
Answer 76.
Yes. By using copy session wizard you can copy a session in a different folder or repository. But that target folder or repository should consists of mapping of that session. If target folder or repository is not having the mapping of copying session, you should have to copy that mapping first before you copy the session
Question 77. What is batch and describe about types of batches?
Answer 77.
Grouping of session is known as batch.
Batches are two types
Sequential: Runs sessions one after the other
Concurrent: Runs session at same time. If you have sessions with source-target dependencies you have to go for sequential batch to start the sessions one after another. If you have several independent sessions u can use concurrent batches. Which runs all the sessions at the same time?
Question 78. Can you copy the batches?
Answer 78. NO
Question 79.How many number of sessions that u can create in a batch?
Answer 79. Any number of sessions.
Question 80.When the Informatica server marks that a batch is failed?
Answer 80. If one of session is configured to “run if previous completes” and that previous session fails.
Question 81. What is a command that used to run a batch?
Answer 81. pmcmd is used to start a batch.
Question 82. What are the different options used to configure the sequential batches?
Answer 82.
Two options
Run the session only if previous session completes successfully.
Always runs the session.
Question 83. In a sequential batch can you run the session if previous session fails?
Answer 83. Yes. By setting the option always runs the session.
Question 84. Can you start a batch with in a batch?
Answer 84.you can not. If you want to start batch that resides in a batch, create a new independent batch and copy the necessary sessions into the new batch.
Question 85. Can you start a session inside a batch individually?
Answer 85. We can start our required session only in case of sequential batch. in case of concurrent batch . we can’t do like this.
Question 86. How can you stop a batch?
Answer 86. By using server manager or pmcmd.
Question 87. What are the session parameters?
Answer 87. Session parameters are like mapping parameters, represent values you might want to change between sessions such as database connections or source files. Server manager also allows you to create user defined session parameters. Following are user defined session parameters.
Database connections
Source file names: use this parameter when you want to change the name or location of session source file between session runs
Target file name: Use this parameter when you want to change the name or location of session target file between session runs.
Reject file name: Use this parameter when you want to change the name or location of session reject files between session runs.
Question 88. What is parameter file?
Answer 88.Parameter file is to define the values for parameters and variables used in a session. A parameter file is a file created by text editor such as word pad or notepad. You can define the following values in parameter file.
Mapping parameters
Mapping variables
Session parameters
Question 89. How can you access the remote source into your session?
Answer 89.
Relational source: To access relational source which is situated in a remote place, you need to configure database connection to the data source.
File Source: To access the remote source file you must configure the FTP connection to the host machine before you create the session.
Heterogeneous: When your maping contains more than one source type, the server manager creates a heterogeneous session that displays source options for all types.
Question 90. What is difference between partitioning of relational target and partitioning of file targets?
Answer 90. If you partition a session with a relational target Informatica server creates multiple connections to the target database to write target data concurrently. If you partition a session with a file target the Informatica server creates one target file for each partition. You can configure session properties to merge these target files.
Question 91. What are the transformations that restricts the partitioning of sessions?
Answer 91. Advanced External procedure transformation and External procedure transformation: This transformation contains a check box on the properties tab to allow partitioning.
Aggregator Transformation: If u use sorted ports u can not partition the associated source
Joiner Transformation: you can not partition the master source for a joiner transformation .Normalizer Transformation XML targets.
Question 92. Performance tuning in Informatica?
Answer 92.The goal of performance tuning is optimize session performance so sessions run during the available load window for the Informatica Server. Increase the session performance by following. The performance of the Informatica Server is related to network connections. Data generally moves across a network at less than 1 MB per second, whereas a local disk moves data five to twenty times faster. Thus network connections often affect on session performance. So avoid network connections.
Flat files: If your flat files stored on a machine other than the Informatica server, move those files to the machine that consists of Informatica server.
Relational data sources: Minimize the connections to sources, targets and Informatica server to improve session performance. Moving target database into server system may improve session performance.
Staging areas: If you use staging areas you force Informatica server to perform multiple data passes. Removing of staging areas may improve session performance. you can run the multiple Informatica servers against the same repository.Distibuting the session load to multiple Informatica servers may improve session performance. Run the Informatica server in ASCII data movement mode improves the session performance. Because ASCII data movement mode stores a character value in one byte. Unicode mode takes 2 bytes to store a character. If a session joins multiple source tables in one Source Qualifier, optimizing the query may improve performance. Also, single table select statements with an ORDER BY or GROUP BY clause may benefit from optimization such as adding indexes. We can improve the session performance by configuring the network packet size, which allows data to cross the network at one time. To do this go to server manger ,choose server configure database connections. If your target consists key constraints and indexes u slow the loading of data. To improve the session performance in this case drop constraints and indexes before you run the session and rebuild them after completion of session. Running a parallel sessions by using concurrent batches will also reduce the time of loading the data. So concurrent batches may also increase the session performance. Partitioning the session improves the session performance by creating multiple connections to sources and targets and loads data in parallel pipe lines. In some cases if a session contains a aggregator transformation, you can use incremental aggregation to improve session performance. Avoid transformation errors to improve the session performance. If the session contained lookup transformation you can improve the session performance by enabling the look up cache. If your session contains filter transformation, create that filter transformation nearer to the sources or u can use filter condition in source qualifier. Aggreagator,Rank and joiner transformation may oftenly decrease the session performance .Because they must group data before processing it. To improve session performance in this case use sorted ports option.
Question 93. What is difference between mapplet and reusable transformation?
Answer 93. Mapplet consists of set of transformations that is reusable. A reusable transformation is a single transformation that can be reusable. If you create a variables or parameters in mapplet that can not be used in another maping or mapplet.Unlike the variables that are created in a reusable transformation can be useful in any other maping or mapplet. We can not include source definitions in reusable transformations. But we can add sources to a mapplet. Whole transformation logic will be hided in case of mapplet.But it is transparent in case of reusable transformation. We cant use COBOL source qualifier, joiner, normalizer transformations in mapplet.Where as we can make them as a reusable transformations.
Question 94. Define Informatica repository?
Answer 94. The Informatica repository is a relational database that stores information, or metadata, used by the Informatica Server and Client tools. Metadata can include information such as mappings describing how to transform source data, sessions indicating when you want the Informatica Server to perform the transformations, and connect strings for sources and targets. The repository also stores administrative information such as usernames and passwords, permissions and privileges, and product version. Use repository manager to create the repository. The Repository Manager connects to the repository database and runs the code needed to create the repository tables. These tables stores metadata in specific format the Informatica server, client tools use.
Question 95. What are the types of metadata that stores in repository?
Answer 95. Following are the types of metadata that stores in the repository
Database connections
Global objects
Mappings/Mapplets
Multidimensional metadata
Reusable transformations
Sessions and batches
Short cuts
Source definitions
Target definitions
Transformations.
Question 96. What is a power center repository?
Answer 96. The Power Center repository allows you to share metadata across repositories to create a data mart domain. In a data mart domain, you can create a single global repository to store metadata used across an enterprise, and a number of local repositories to share the global metadata as needed.
Question 97. How can you work with remote database in informatica?did you work directly by using remote connections?
Answer 97. To work with remote data source you need to connect it with remote connections. But it is not preferable to work with that remote source directly by using remote connections .Instead you bring that source into your local machine where Informatica server resides. If you work directly with remote source the session performance will decreases by passing less amount of data across the network in a particular time.
Question 98. What are the scheduling options to run a session?
Answer 98. You can schedule a session to run at a given time or interval, or you can manually run the session.
Different options of scheduling
Run only on demand: server runs the session only when user starts session explicitly
Run once: Informatica server runs the session only once at a specified date and time.
Run every: Informatica server runs the session at regular intervals as you configured.
Customized repeat: Informatica server runs the session at the dates and times specified in the repeat dialog box.
Question 99. What is tracing level and what are the types of tracing level?
Answer 99. Tracing level represents the amount of information that Informatica server writes in a log file.
Types of tracing level
Normal
Verbose
Verbose init
Verbose data
Question 100. What is difference between stored procedure transformation and external procedure transformation?
Answer 100. In case of stored procedure transformation procedure will be compiled and executed in a relational data source. You need data base connection to import the stored procedure in to your maping.Where as in external procedure transformation procedure or function will be executed out side of data source. If you need to make it as a DLL to access in your mapping. No need to have data base connection in case of external procedure transformation.
