Top 70 Teradata Interview Questions

teradata questions
1. Difference between Teradata and Other RDBMS?
2. Draw the picture of Teradata warehouse?
3. What are the differences between Star schema and Snow flake schema?
4. Differentiate Dimension table and Fact table?
5. What is Fact less fact table?
6. Describe the different types of dimension tables? And explain with
Examples?
7. Explain Teradata important components with architecture?
8. Difference between SMP and MPP?
9. Explain the Shared nothing architecture?
10.What is a set table?
When we will use multiset table?
11.What is the usage of Fallback?
12.How many primary keys we will apply on a table?
13.How does rows store in Teradata?
14.Tell me the types of Indexes?
15.Difference between UPI and NUPI and the situation where exactly
We will use these.?
16.The role of SI in teradata and explain the types?
17. How do we create a join and hash indexes and explain the scenerios?
When we will use exactly?
18.What is the meaning of Transient journal overhead?
19.What is skewness in teradata?
20.What is a subtable and when it requires?
21.What is the usage of coalesce function?
22.When we will use null-if function?
23. Can you write the syntax of substring and case expression.?
24.What are the different types of tables?
25.Explain the differences between global temporary table and volatile table?
26.Describe the use of Explain command and its features?
27.Have you collected statistics in your project?
28.Difference between FastLoad and Multiload?
29.Difference between BTEQ export and Fast Export?
30.Difference between general Delete and Multiload delete?
31.What is the structure for importing a file in BTEQ?
32.What is the structure for importing a file in Fastload?
33.What is the structure for importing a file in Multiload?
34.What is the structure for importing a file in Tpump?
35.How do you pass multiple files in fastload and multiload?
36.Explain different phases of fastload?
37.Explain the phases in multiload?
38.Describe the error tables in fastload with structures?
39.Describe the error tables in multiload with structures?
40.Difference between multiload and Tpump?
41.What is the use of Error code and Activitycount in Bteq?
42.How do you run the scripts in unix environment and windows
Environment?
43.How do you handle the errors in ER and UV tables?
44.How do you check the status of scripts ruined?
45.Tell me the limitations of multiload?
46.Tell me the limitations of fastload?
47.What is the usage of filler in multiload?
48.What is the DIF format and when we will use?
49.Difference between Subquery and Corelated sub query?
50.What is a node and how many node system you have in your project?
51.What are the various ways to execute a query in teradata?
52.What is the difference between procedure and function?
53.What is the difference between macro and procedure?
54.What is a view and how it is useful?If so have you created any
Views in your project?
55.What are join strategies?Explain clearly with examples?
56.Have you done any performance tuning in your project if so
How do start?
57.What the various ways to tune a teradata query?
58. How do you select an index for a table?
59.Write a query for finding second maximum salary?
60.Write a query for a.finding duplicate rows?
b.removing duplicate rows?
c.keeping in another table?
61.There are two tables called customer table and calls table.
If a customer made a call, that record should be there in calls table.
I need the details of customers who didn’t made any call?Write a query?
62.I have two tables called emp and dept.thers is relationship between
Deptcode. I need all deptcodes and their corresponding employees?
63.Write a view with more then one table?
64.How do you handle if multiload script got failed in acquisition phase?
65.How do you handle if multiload script got failed in apply phase?
66.How do you handle if fastload script got failed in first phase?
67.How do you handle if fastload script got failed in second phase?
68.How do you handle Bteq script failures?
69.How do you pass parameters to a fastexport script?
70.Describe the layout of multiload?

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