Friday, September 18, 2009

Which transformation should we use to normalize the COBOL and relational sources?

Normalizer Transformation

When U 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

Thursday, September 17, 2009

Difference between static cache and dynamic cache

Static cache Dynamic cache

U can not inert or update the cache. U can insert rows into the cache as u pass

to the target

The informatic server returns a value from The informatic server inserts rows into cache

the lookup table opr cache when the condition when the condition is false.This indicates that

is true.When the condition is not true,the the row is not in the cache or target table

informatica server returns the default value U can pass these rows to the target table

for connected transformations and null for

unconnected transformations

Wednesday, September 16, 2009

What r the types of lookup caches?

Persistent cache: U 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,U can configure the lookup transformation to rebuild the lookup cache

Static cache: U 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 prosesses the lookup transformation

Dynamic cache: If u want to cache the target table and insert new rows into cache and the target,u can create a look up transformation to use dynamic cache.The informatica server dynamically inerts data to the target table

shared cache: U can share the lookup cache between multiple transactions.U can share unnamed cache between transformations inthe same maping

Tuesday, September 15, 2009

what is meant by lookup caches?

The informatica server builds a cache in memory when it processes the first row af a data in a cached look up transformation.It allocates memory for the cache based on the amount u configure in the transformation or session properties.The informatica server stores condition values in the index cache and output values in the data cache

Monday, September 14, 2009

Differences between connected and unconnected lookup?

Connected lookup Unconnected lookup

Receives input values diectly from Receives input values from the result of a

the pipe line. lkp expression in a another transformation

U can use a dynamic or static cache U can use a static cache

Cache includes all lookup columns Cache includes all lookup out put ports in the

used in the mapping lookup condition and the lookup/return port

Support user defined default values Does not support user defiend default values

Sunday, September 13, 2009

Why use the lookup transformation ?

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.

Saturday, September 12, 2009

What is the look up transformation?

Use lookup transformation in u'r mapping to lookup data in a relational table, view, 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

Thursday, September 10, 2009

What r the join types in joiner transformation?

Normal (Default)

Master outer

Detail outer

Full outer

Wednesday, September 9, 2009

What r the settings that u use to configure the joiner transformation?

Master and detail source

Type of join

Condition of the join

Tuesday, September 8, 2009

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 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.

Monday, September 7, 2009

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 transformation.Where as u doesn't need matching keys to join two sources

Two relational sources should come from same datasource in sourcequalifier.U can join relatinal sources which r coming from diffrent sources also

Sunday, September 6, 2009

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 caches in memory to process the transformation.If the informatica server requires more space,it stores overflow values in cache files

Saturday, September 5, 2009

Can u use the maping parameters or variables created in one maping into any other reusable transformation?

Yes.Because reusable tranformation is not contained with any maplet or maping

Can U use the maping parameters or variables created in one maping into another maping?


We can use mapping parameters or variables in any transformation of the same maping or mapplet in which U have created maping parameters or variables

Friday, September 4, 2009

What r the mapping paramaters and maping variables?

Maping parameter represents a constant value that U can define before running a session.A mapping parameter retains the same value throughout the entire session

When u use the maping parameter ,U declare and use the parameter in a maping or maplet.Then define the value of parameter in a parameter file for the session

Unlike a mapping parameter,a maping variable represents a value that can change throughout the session.The informatica server saves the value of maping variable to the repository at the end of session run and uses that value next time U run the session

Thursday, September 3, 2009

What r the unsupported repository objects for a mapplet?

COBOL source definition

Joiner transformations

Normalizer transformations

Non reusable sequence generator transformations

Pre or post session stored procedures

Target definitions

Power mart 3.5 style Look Up functions

XML source definitions

IBM MQ source definitions

Wednesday, September 2, 2009

What r the methods for creating reusable transforamtions?

Two methods

1.Design it in the transformation developer

2.Promote a standard transformation from the mapping designer.After U add a transformation to the mapping , U can promote it to the status of reusable transformation

Once U promote a standard transformation to reusable status,U can demote it to a standard transformation at any time

If u change the properties of a reusable transformation in mapping,U can revert it to the original reusable transformation properties by clicking the revert button

Tuesday, September 1, 2009

What r the reusable transformations?

Reusable transformations can be used in multiple mappings.When u need to incorporate this transformation into maping,U add an instance of it to maping.Later if U change the definition of the transformation ,all instances of it inherit the changes.Since the instance of reusable transforamation is a pointer to that transforamtion,U can change the transforamation in the transformation developer,its instances automatically reflect these changes.This feature can save U great deal of work