Use caution when opting to use advanced techniques instead of the recommended explicit mapping techniques offered in the Property Mapper editor.
There are several advanced mapping techniques, available on the Property Mapper editor's Advanced tab, that you can use when building prototypes. This section describes these techniques and provides information on the priority order that the Data Foundry uses when applying them.
This type of mapping enables implicit mapping. When implicit mapping is enabled, any source property that has a name that is identical to an existing dimension is automatically mapped to that dimension.
The setting Map Source Properties to Endeca Dimensions with the Same Name (located on the Property Mapper editor's Advanced tab) enables implicit mapping. The like-named dimension, and any of its constituent dimension values, must already exist in your dimension hierarchy (in other words, you've already defined them using the Dimensions and Dimension Values editors).
Implicit mapping uses the Normal mapping mode where only those source property values that have a matching dimension value explicitly defined in the dimension hierarchy are mapped. Forge assigns the IDs for any matching dimension values to the Endeca records. Any source property values that do not have matching dimension values in the dimension hierarchy are ignored.
Implicit mapping is limited to mappings between source properties and dimensions. Implicit mapping cannot take place between source properties and Endeca properties.
The Property Mapper editor’s Advanced tab lets you map source properties to either Endeca properties or dimensions if no mapping is found.
The Property Mapper editor's Advanced tab contains the following option:
This option defines the default that Forge uses to handle source properties that have neither explicit nor implicit mappings. There are three possible settings:
Uncheck the option altogether to ignore source properties that do not have an explicit or implicit mapping defined.
Check Property to create a mapping between the source property and an Endeca property. Forge does this by creating a new Endeca property that uses the same name and value as the source property and assigning it to the record.
Check Dimension to create a mapping between the source property and a dimension. Forge does this by creating a new dimension, using the source property's name. Forge uses the Auto Generate mode to populate the dimension with dimension values that match the source property's values.
Use the default mapping option with caution because:
With this option enabled, all source properties will ultimately be mapped and mapped properties use system resources. Ideally, you should only map source properties that you intend to use in your implementation so that you minimize the use of system resources.
Many production-level implementations automatically pull and process new data when it is available. If this data has new source properties, these properties will be mapped and included in your MDEX Engine indices. Again, this uses system resources unnecessarily but, perhaps more importantly, this situation may also result in the display of dimensions or Endeca properties that you do not want your users to see.
Forge looks for explicit mapping and attempts implicit mapping between source property and a like-named dimension if the explicit mapping not exist. Forge defaults to the selected If No Mapping is Found option if neither explicit nor implicit mapping exists.
Forge uses this prioritization when mapping source properties:
First, Forge looks for an explicit mapping for the source property.
If no explicit mapping exists, and Map Source Properties to Endeca Dimensions with the Same Name is enabled, Forge will try to create an implicit mapping between the source property and a like-named dimension.
If no explicit or implicit mapping exists, Forge uses the If No Mapping is Found, Map Source Properties to Endeca: Properties/Dimensions option to determine how to handle the mapping.
Explicit null mappings provide a means to prevent an implicit or default mapping from being formed for a particular source property.
In other words, you can enable either implicit or default mapping, and then turn off mapping altogether for selected source properties using explicit null mappings.
The Default Maximum Length option, on the Advanced Tab of the Property Mapper, defines the maximum source property value length allowed when creating mappings.
Source properties that have values that exceed this length are not mapped, and a warning is issued by Forge.
If you do not explicitly specify a Default Maximum Length, Forge does the following:
If you do explicitly specify a Default Maximum Length, that length is applied to both Endeca property and dimension mappings.
You can override the Default Maximum Length on a per mapping basis using the Maximum Length field in both the Property Mapping and Dimension Mapping dialog boxes. For example, you can use the Default Maximum Length to limit the length of all your source properties, but set an override for a Description source property that allows the description to be as long as necessary.
