MINIMUM is valid for character data as well as numeric data. MINIMUM returns the lowest sort order of a character expression.
The computation does not include nulls. For more information, see “Manipulating Nulls” in Teradata Vantage™ - SQL Fundamentals, B035-1141 and Aggregates and Nulls.
If value_expression specifies a column expression, the expression must refer to at least one column in the table from which data is selected.
If value_expression specifies a column reference, the column must not be a view column that is derived from a function.