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Configuring Fallback Strategies for Survivorship Rules

This topic contains information about fallback strategies for survivorship rules.

You can set a fallback strategy for survivorship rules. For example, if you have a source system survivorship rule for an attribute, and you have two records from the same source system involved in a merge, Reltio would generate two Operational Values (OVs) for the attribute. To get a single OV, you can specify the fallback strategy as a tiebreaker .

Fallback strategies can be any attribute survivorship rule (see Design survivorship rules for more information). Also, you can list more than one strategy as a fallback, with preference given to strategies ordered first.

Important: Fallback Strategies are not inherited from other attributes. Each Attribute must have its own set of Fallback Strategies defined separately.
Important: DEPRECATION NOTICE: As of 04/11/2017, fallbackStrategiesChain is deprecated, and you now use fallbackStrategies.

To configure fallback strategies, you can use the survivorshipGroups section of the L3 configuration file to specify the values for fallBackStrategies.

Example

Fallback strategies provide flexibility to change an OV rule for some other attribute. In the following example, in case of fallback for LastName, you can change the rule for the FirstName attribute.
{
   "survivorshipGroups":[
      {
         "URI":"configuration/entityTypes/HCP/survivorshipGroups/default",
         "default":true,
         "mapping":[
            {
               "attribute":"configuration/entityTypes/HCP/attributes/FirstName",
               "sourcesUriOrder":[
                  "configuration/sources/HMS",
                  "configuration/sources/AHA",
                  "configuration/sources/Reltio"
               ],
               "survivorshipStrategy":"SRC_SYS"
            },
            {
               "attribute":"configuration/entityTypes/HCP/attributes/MiddleName",
               "survivorshipStrategy":"OtherAttributeWinnerCrosswalk",
               "primaryAttributeUri":"configuration/entityTypes/HCP/attributes/FirstName"
            },
            {
               "attribute":"configuration/entityTypes/HCP/attributes/LastName",
               "survivorshipStrategy":"OtherAttributeWinnerCrosswalk",
               "primaryAttributeUri":"configuration/entityTypes/HCP/attributes/FirstName",
               "fallbackStrategies":[
                  {
                     "attribute":"configuration/entityTypes/HCP/attributes/LastName",
                     "survivorshipStrategy":"SRC_SYS",
                     "sourcesUriOrder":[
                        "configuration/sources/HMS",
                        "configuration/sources/Reltio",
                        "configuration/sources/AHA"
                     ]
                  }
               ],
               "fallbackUsingCriteria":"ZERO_OR_MORE_THAN_ONE"
            }
         ]
      }
   ]
}
Note: The default value of the new survivorship strategy option fallbackUsingCriteria is MORE_THAN_ONE, which is used for backward compatibility. ZERO_OR_MORE_THAN_ONE means that the fallback rule applies to the result of the primary survivorship rule if there are either zero or more than one Operational Values.