The pivot table makes use of the set data types Column Selector and Order
Specifier.
These set data types are defined:
- Column Selector
- The column selector is a comma-separated list of positive integers numbering 0 for the first
column and n-1 for the last column in a table of n columns.
- Example: Given a table with four columns, a column selection of "0,3,1" selects the first, the
last and the second column.
- Order Specifier
- The order specifier is a comma-separated list of positive integers numbering 0 for the first
column and n-1 for the last column in a table of n columns. Positive values specify ascending,
negative values descending order.
- Example: Given a table with four columns, a order specifier of "-0,3" specified an descending
order on the first column and a ascending order on the last column.
There is a difference between not setting a value and specifying an empty value. The empty value
always means the empty set. Not setting a value may mean selecting all or nothing, depending on the
context.