Nested
Lookups and Multi-Level Search-within-a-Search
Lookup fields can appear not only in the main table but also within any of the lookup tables themselves, such as when the Manufacturer field in the main table is a lookup into the Manufacturers table of legal manufacturer names, and the Statefield in the Manufacturers table is in turn a lookup into the Statestable of legal two-letter state abbreviations.
In the MDM Client, each lookup field in a lookup table appears not only as a search tab when the current table is the lookup table, but also within the search tab for the main table lookup field when the current table is the main table, for multi-level “search-within-a-search.”
A single nested lookup field allows the main table lookup field to support search-within-a-search. Multiple nested lookup fields not only support search-within-a-search, they also allow the lookup table to act as a valid table that defines specific value combinations among the values of each of the multiple nested lookup fields.
Like all MDM drilldown searches, multi-level search-within-a-search is omnidirectional; that is, you can make nested lookup field value selections in any order and intermingle them with selections made from other search dimensions.
If the search tab corresponds to a lookup field into a table that contains one or more nested lookup fields, the tab is split into three subpanes, as shown in the figure below.
The top left Lookups subpane lists the lookup fields of the lookup table itself, and the top right Values subpane contains the list of values for the selected nested lookup field. Finally, the bottom subpane contains the list of lookup table values (narrowed down based on the selections of values for the lookup fields of the lookup table).
You can select lookup field values in the bottom subpane at any time, just as if the lookup field did not have nested lookups. Or you can first select nested lookup field values in the Values subpane to narrow down the list of lookup field values, for search-within-a-search.
As you select each nested lookup field in the Lookups subpane, the list of values in the Valuessubpane changes to correspond to the set of values for the selected nested lookup field.
As you select values for a nested lookup field, the list of lookup field values in the bottom subpane and the set of records in the Records pane are both narrowed down at the same time.
A lookup field with just a single nested lookup that is the only display field does not require multi-level search-within-a-search (since the set of nested lookup values and the set of lookup values is identical), and offers the standard search tab without the Lookups and Values subpanes.