Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

Why Multiload does not supports USI and supports NUSI?

Answer Posted / reddy

MulitLoad has support for Non-Unique Secondary Indexes
(NUSIs) since NUSIs are AMP Local. They have subtable
within base table. It has no hash bucket to redirect to
another amp, everything points to their own amp (AMP Local)
If you go with USI, it has hash bucket, which might
redirect to another amp, more possibilites for full table
scan.

Motive for avoiding Indexes(other thn NUSI): Avoid Full
table scan. whenever we define a SI an SI subtable is
created in each AMP.For USI they go for a hash
distribution, and hence the actual data row pointed by the
USI subtable rows in one AMP may not be in the same AMP as
the subtable..so the AMPs
have to communicate, which is not supported by Multiload.
For NUSI the subtable will store references of only those
actual data rows who exist in the same AMP as the
subtable..they all point to the data in their own
AMP..hence AMPs dont need to communicate here.
Thus the AMPs work in parallal with NUSI and hence Mload
supports that.

Is This Answer Correct ?    5 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is a three-tier data warehouse?

1053


Explain the term 'columns' related to relational database management system?

985


Describe the between keyword in teradata?

979


What is meant by Teradata Gateway?

1002


Highlight the differences between Primary Key and Primary Index.

1016


How is MLOAD Teradata Server restarted after execution?

1165


What are the different design perspectives used in teradata?

925


What is node? How many nodes and amps used in your previous project?

1060


What are the enhanced features in teradata v2r5 and v2r6?

1078


What are the functions of a teradata dba?

1019


What is meant by a Clique?

989


What are the components provided on node?

984


How to select first n records in teradata?

1039


Explain the teradata primary index mechanics in detail with a diagram.

909


why use references rather than pointers in the public api, particularly for arguments which are modified?

935