Interested to Buy Any Domain ? << Click Here >> for more details...
Hi frnds this question is asked at IBM
One query is there when we dont collect stastics on
it,exlapin will show us LOW CONFIDENCE,When we collect
stastics it shows HIGH CONFIDENCE.WHAT IS THE INTERNAL
ARCHITECTURE ACTUALLY GOING ON ?????ASKED ON 23-08-2012
THANKS IN ADVANCE
- 2 Answers
- 6542 Views
- IBM, I also Faced
- E-Mail Answers
Answer Posted / tdguy
statistics collection is a concept, where TD stores the
demographic data and stores. When generating the explain
plan, TD looks for the stats for the columns used in the
sql., particularly the columns used on both sides of the
join. TD prepares a estimate based on the data available.If
enough stats are not available, TD displays a low
confidence. Whereas, if stats are collected for columns
involved in sql, stats will be available for TD, which in
turn displays a high confidence, which means exact or close
approximate no of rows processed will be displayed.
| Is This Answer Correct ? | 6 Yes | 0 No |
Post New Answer View All Answers
Difference between multiload and tpump?
What happens in a conflict? How do you handle that?
Explain Teradata performance tuning and optimization?
What is a level of granularity of a fact table?
Hi Friends, Please send me Teradata Materials for certifications Thanks in advance !!
Steps to create a data model?
What are the functions of a Parser?
What are the various indexes in teradata? Why are they preferred?
What is meant by a Virtual Disk?
What is the opening step in basic teradata query script?
How can bottlenecks be identified?
Describe the between keyword in teradata?
What are some commonly used bteq scripts?
What are the different design perspectives used in teradata?
How will you solve the problem that occurs during update?
