A transform turns values into other values. These are usually used in the contet of a ColumnSet, followed by + and a Transform,
as in ColumnSet+Transform
Transforms can be chained together with a +, and so you can have. ColumnSet+Transform1+Transform2+Transform3.
Such a ColumnSet selects the same columns as before, but produces each value indivually transformed.
Transform syntax is a period delimited list, consisting of zero or more modifiers plus one transform, optionally followed by a comma and a pattern specific to the particular transform.
lower applied to “NÑ” produces “nÑ”, whereas ‘utf8.lower’ applied to the same string yields “nñ”.url or binhex.url or binhex.