In Teradata using case statement, you can specify an alternative value for a conditional expression based on the equality comparison that evaluates to true. Basically you represent some data based on different conditions.
Teradata sum returns a column value that is the arithmetic sum of value_expression.
To get sum over partition by Teradata you can use the aggregate function SUM and PARTITION BY on a required column.
Teradata skew function returns the skewness of the distribution of value_expression.
In Teradata MIN function is used to get minimum value for a value_expression.
In Teradata Max function is used to get maximum value for a value_expression.
In Teradata having clause is a conditional expression that must be satisfied for a group of rows to be included in the result data.
Count returns a value that is the total number of qualified rows in value_expression.
AVG is an aggregate function that returns arithmetic average of all values in value_expression. This is used in conjunction with GROUP BY clause.
Teradata SUBSTRING or SUBSTR function extracts a substring from another string based on the position.