Filter transformation to filter the data only one condition and drop the rows don’t meet the condition.
Drop rows does not store any ware like session log file..
Router transformation to filter the data based on multiple conditions and give yiou the option to route rows that don’t match to a default group.
Explain bulk loading?
You can use bulk loading to improve performance of a session that inserts a large amount of data to a db2,sysbase,oracle or MS SQL server database.
When bulk loading the power center server by passes the database log,which speeds performance.
With out writing to the database log, however the target database can’t perform rollback. As a result you may not be perform recovery.
When you select this option the power center server orders the target load on a row-by-row basis only.
Edit tasks->properties->select treat source rows as insert.
Edit tasks->config object tab->select constraint based
If session is configured constraint absed loading when target table receive rows from different sources.The power center server revert the normal loading for those tables but loads all other targets in the session using constraint based loading when possible loading the primary key table first then the foreign key table.
Use the constraint based loading only when the session option treat rows as set to insert.
Constraint based load ordering functionality which allows developers to read the source once and populate parent and child tables in a single process.
what is transformation?
Transformation is repository object that generates modifies or passes data.
what are the type of transformations?
2 types:
1) active
2) passive.
Explain active and passive transformation?
Active transformation can change the number of rows that pass through it.No of output rows less than or equal to no of input rows.
Passive transformation does not change the number of rows.Always no of output rows equal to no of input rows.
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