For tables, cell values in any column or row can become columns or rows {pivoting}|. The new table shows a different perspective on data, along a new dimension. Pivoting can correlate two table variables.
empty cells
Cells can be empty (NULL). Pivoting treats NULL the same as other cell values. Pivoting can make fewer cells and so fewer NULL cells.
example
Table has Days columns D1, D2, ... and Persons rows P1, P2, ... Table cells have Locations L1, L2, ..., with L1 in D1-P1 cell, and so on. See Figure 1. You can pivot table to make table with Days columns, Locations rows, and Persons in cells. See Figure 2. Cells fill by rule: Days and Locations have Persons. You can always pivot new table back to old table.
data rows
You can pivot table on one column to put another column in cells. For example, table can have Day, Location, People, Thing, and Amount columns. Row records are Days, Places, People, Things, and Amounts combinations. You can pivot on Day column and rows, to put Amount in cells. Now table rows are Thing, People, and Place combinations, and columns are Day values listed in original-table cells. Cell Amount matches Day, Place, People, and Thing. If new table has same or greater cell number as original table, you can pivot back to original table.
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Date Modified: 2022.0224