What is Join Index in TD and How it works?
Answer Posted / veni botcha
JOIN INDEX:
-----------
Join Index is nothing but pre-joining 2 or more tables or
views which are commonly joined in order to reduce the
joining overhead.
So teradata uses the join index instead of resolving the
joins in the participating base tables.
They increase the efficiency and performance of join queries.
They can have different primary indexes than the base tables
and also are automatically updated as and when the base rows
are updated. they can have repeating values.
There are 3 types of join indexes:
1)Single table join index - here the rows are distributed
based on the foreign key hash value of the base table.
2) Multi table join index - joining two tables.
3) Aggregate join index - performing the aggregates but only
sum and count.
| Is This Answer Correct ? | 43 Yes | 9 No |
Post New Answer View All Answers
Write a program to show the parser component used in teradata?
i learn teradata,it is so intersting,now i want teradata certifications ,so any 1 help me to get teradata certifications TD 12 ? email:kdcrazyy@gmail.com
Can any one explain me the difference between BTEQ and MLOAD,TUMP. All canbe used for same purpose but still differnt methods. why ?
Can we collect statistics on multiple columns?
If the PMON is not working then how do you identify and monitor all the processes, resources and sessions ?
Explain and compare pros and cons of start schemas?
What do you mean by caching in teradata?
Explain some differences between mpp and smp?
What are the design features involved in teradata?
Explain BYNET.
Explain the term 'columns' related to relational database management system?
Define views in teradata with syntax.
What is basic teradata query language?
Explain teradata architecture in detail with a diagram.
Can you fastexport a field, which is primary key by putting equality on that key?