Teradata Teradata SQL 3

Question 1

What is the role of the GROUP BY clause in a Teradata SELECT statement?

Accepted Answer

Groups rows sharing common column values for aggregate calculations

Answer

GROUP BY organizes rows that share the same values in specified columns into summary groups, enabling aggregate functions to operate on each group.

Question 2

Which Teradata SQL statement is used to change an existing table's structure, such as adding a column?

Accepted Answer

ALTER TABLE

Answer

ALTER TABLE modifies an existing table's structure, allowing operations like adding, dropping, or modifying columns.

Question 3

What does the BETWEEN operator do in a Teradata WHERE clause?

Accepted Answer

Tests whether a value falls within an inclusive range

Answer

BETWEEN tests whether a value is within a specified inclusive range, equivalent to value >= low AND value <= high.

Question 4

In Teradata, which window function assigns a unique sequential integer to each row within a partition?

Accepted Answer

ROW_NUMBER()

Answer

ROW_NUMBER() assigns a unique consecutive integer starting at 1 to each row within a partition, with no ties.

Question 5

Which Teradata SQL command permanently saves changes made during a transaction?

Accepted Answer

COMMIT

Answer

COMMIT (or ET in BTEQ) permanently writes all changes made since the last commit or start of the transaction to the database.

Teradata Practice Test