Interview Questions : DataWareHouse - Part 4

What are the types of Synonyms?
There are two types of Synonyms Private and Public

What is a Redo Log?
The set of Redo Log files YSDATE, UID, USER or USERENV SQL functions, or the pseudo columns LEVEL or ROWNUM.

What is an Index Segment?
Each Index has an Index segment that stores all of its data.

Explain the relationship among Database, Table space and Data file?
Each databases logically divided into one or more table spaces one or more data files are explicitly created for each table space.

What can you delete to free up disk space in IBM InfoSphere Information Server

What can you delete to free up disk space in IBM InfoSphere Information Server when disks are becoming full?

What to do ????

Here are some things you can do to clean up space:

• Clear the &PH& file in the Project directory. There is a &PH& directory in each DataStage project directory, which contains information about active stages that is used for diagnostic purposes. The &PH& directory is added to every time a job is run, and needs periodic cleaning out.
  

Managing and Deleting Persistent Data Sets within IBM InfoSphere Datastage

Data Sets sometimes take up too much disk space. This technote describes how to obtain information about datasets and how to delete them.

 

Data sets can be managed using the Data Set Management tool, invoked from the Tools > Data Set Management menu option within DataStage Designer (DataStage Manager in the 7.5 releases.) Alternatively, the 'orchadmin' command line program can be used to perform the same tasks.

The files which store the actual data persist in the locations identified as resource disks in the configuration files. These files are named according to the pattern below:

descriptor.user.host.ssss.pppp.nnnn.pid.time.index.random