Interested to Buy Any Domain ? << Click Here >> for more details...
I have a table with emp id, emp name, dept id and sal where
dept id is NUSI. SEL * FROM EMP WHERE DEPTID = 100. Can any
one explain how it will fetch the record.
- 4 Answers
- 10292 Views
- I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / ajain
Whenever NUSI is created, subtable will be created for each AMP's with the fields rowid and secondary index value.For NUSI ,subtable will be AMP local ie it will be having the records which are specific to the particular AMP.
When someone queries with the NUSI, all the AMPs will search in their own subtable for particular secondary index .For AMPs which found the particular record in their subtable ,it will retrieve the actual data from the AMP and PE will be consolidating the records and give to user
Since NUSI involves all AMP operation , PE will be deciding whether FULL table scan or ALL AMP operation will be more efficient .
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / saravanan
If COLLECT STATS has been defined on the table EMP, then PE
will avoid going for a FULL TABLE SCAN.
If not, PE will undergo a FULL TABLE SCAN to fetch
DEPTID=100
| Is This Answer Correct ? | 4 Yes | 2 No |
Answer / siva reddy
in case we are using nusi in this swicthvation subtable is created same amps.it is one of the full table scan but not full table scan.it's scan only all amps sub table.if any one of the match it will disply.here no allgorithem can be performed.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / saravanan
If your question is about how Parsing engine would fetch
DEPTID=10, it will undergo a FULL TABLE scan since Dept_Id
is a Non unique secondary index.
| Is This Answer Correct ? | 1 Yes | 6 No |
hi guys...i have good experiance in oracle ...now i want to learn teradata? how much of percentage my knowledge is used to understand the teradata? i mean.. if teradata also having sql queries or not?
How do you Generate Sequence in Teradata?
how many modules are there in telecome domain?how to explain the architecture?
When tpump is used instead of multiload?
Fast Load Script is failed and error tables are available then how do you restart?
Aborted in Phase 2 data acquistion completed in fastload?
Explain and compare pros and cons of snow flake schemas?
What is the diffrence between Multiload & Fastload interms of Performance?
How can you track login parameters of users in teradata?
What are the advantages of teradata?
Hi friends This is suneel and i am new to teradata. In both situvations teradata administrator and teradata sql assitant 12.0 1)How to create database in teradata and under database how to create user. 2)How to create table under that user and giving privilizes to that user. Thanks alot.
Suppose i have data like 2009/12/31 555555534 ' ' Generally last 2 records are wrong format it is going to error table but i don't want load error table if any wrong format in Date column Pass "NULL" how can we do it fast load
Teradata 
