Question { Datamatics, 7999 }

What does mknod do? What?s a named pipe?

Answer

in linux system everything includind hardware is a file. the
coomand mknod,mkfifo craetes these special files like block
files for a disk which can take multiple inputs
simultaneously or a special character file denoted by c
which can take one input at a time

names pipes(also known as fifo) are special pipes these are
used for interprocess communication. suppose you have written
ps -e |less in this example the output of the ps -e coomand
will be temporaroly moved to temporary file created by this
pipe and you will be able to see the data. but as soon as
this process ends this file will be ended. but the files
created by named pipes will not be deleted. named pipes are
created using the command mkfifo or mknod. named pipes are
system persistant.

Question { HCL, 51851 }

how to see unallocated hard disk space on linux

Answer

df -h /dev/devicename
device name could be hda,sda

Question { Accenture, 11463 }

What does "bulk loading of a table" mean? Can you describe
advantages or disadvantages of using these features?

Answer

Loading bulk data into tables is one of the most common
tasks in data warehouse applications. As the data volume
increases, so does the complexity of the loading process.
While loading bulk data, you should not only consider how
much time it takes to load the data, but also consider the
concurrency and data availability requirements, and the
maintenance operations, such as creating or rebuilding
indexes. Bulk data loading can take a significant amount of
time. Therefore, you should consider the options that enable
fast loading of data. However, loading fast is not enough.
Loading bulk data can, at times, cause escalation of locks
and impact other concurrent transactions on the table. For
applications requiring concurrent data access during load,
you should consider options that provide the desired
concurrency. Availability of existing data while the new
data is being loaded is also an important consideration to
help you choose the right option. Creating and rebuilding
indexes is an essential part of the data loading process,
but can be time-consuming for large tables. However, there
are ways to create indexes on the freshly loaded data
without impacting the data in the rest of the table.SQL
Server 2005 provides partitioned tables, and while loading
data into a partitioned table, you can have several options.
Each option provides its own distinct advantages, but the
option you choose depends upon the requirements of your
application, such as performance, concurrency, temporary
storage, and so on

Question { Accenture, 9122 }

What is a "parameter card" and what is useful for?

Answer

parateter card is a type of card used to provide voice
digital communication to radio stations for therir FMs