Questions V

Why you use repository connectivity?
When you edit,schedule the sesion 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.
Briefly explian the Versioning Concept in Power Center 7.1.
When you create a version of a folder referenced by shortcuts, all shortcuts continue to reference their original object in the original version. They do not automatically update to the current folder version.
For example, if you have a shortcut to a source definition in the Marketing folder, version 1.0.0, then you create a new folder version, 1.5.0, the shortcut continues to point to the source definition in version 1.0.0.
Maintaining versions of shared folders can result in shortcuts pointing to different versions of the folder. Though shortcuts to different versions do not affect the server, they might prove more difficult to maintain. To avoid this, you can recreate shortcuts pointing to earlier versions, but this solution is not practical for much-used objects. Therefore, when possible, do not version folders referenced by shortcuts.

What is source qualifier transformation?
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 represents the rows that the Informatica Server reads when it executes a session.
Join data originating from the same source database. You can join two or more tables with primary-foreign key relationships by linking the sources to one Source Qualifier.
Filter records when the Informatica Server reads source data. If you include a filter condition, the Informatica Server adds a WHERE clause to the default query.
Specify an outer join rather than the default inner join. If you include a user-defined join, the Informatica Server replaces the join information specified by the metadata in the SQL query.
Specify sorted ports. If you specify a number for sorted ports, the Informatica Server adds an ORDER BY clause to the default SQL query.
Select only distinct values from the source. If you choose Select Distinct, the Informatica Server adds a SELECT DISTINCT statement to the default SQL query.
Create a custom query to issue a special SELECT statement for the Informatica Server to read source data. For example, you might use a custom query to perform aggregate calculations or execute a stored procedure.

What is a source qualifier?-
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 represents the rows that the Informatica Server reads when it executes a session.

What is source qualifier transformation?
When you 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 informatica server reads when it runs a session.

What is incremantal aggregation?
When using incremental aggregation, you apply captured changes in the source to aggregate calculations in a session. If the source changes only incrementally and you
can capture changes, you can configure the session to process only those changes. This allows the Informatica Server to update your target incrementally, rather than
forcing it to process the entire source and recalculate the same calculations each time you run the session.

If you are workflow is running slow in informatica. Where do you start trouble shooting and
what are the steps you follow?
When the work flow is running slowly u have to find out the bottlenecks
in this order target source mapping session system

What is exact use of 'Online' and 'Offline' server connect Options while defining Work flow in Work flow monitor? . The system hangs when 'Online' server connect option. The Informatica is installed on a Personal laptop.
When the repo is up and the PMSERVER is also up, workflow monitor always will be connected on-line.
When PMserver is down and the repo is still up we will be prompted for an off-line connection with which we can just monitor the workflows

Explain about perform recovery?
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 bypasses 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.

How the informatica server sorts the string values in Ranktransformation?
When the informatica server runs in the ASCII data movement mode it sorts session data using Binary sortorder.If you configure the seeion to use a binary sort order,the
informatica server caluculates the binary value of each string and returns the specified number of rows with the higest binary values for the string.