Changing a Column Data Type
In general, the following requirements apply to changing a column's data type:
The change must not require storage reorganization. After you modify a column's data type, data that you load conforms to the new definition.
The column must not be referenced in the segmentation expression of any table projection.
You can change the width of columns within the same class of data type. Vertica supports reducing column widths within the data type class if the following conditions are true:
- Existing column data is no greater than the new width.
- All nodes in the database cluster are up.