Alternate Key is an index used alternatively in place of primary key of the object. This helps to identify records using different field combination other than the fields of default/primary index of the object. Maximo offers the ability to have alternate index/key at object and object structure level

Steps to enable alternate key in object structure :
 
Step 1 : Note down the desired index name for the object from Database Configuration application (Indexes Tab)
Step 2 : Navigate to Integration -> Object Structure
Step 3 : Select the object structure you wish to enable the alternate key 
Step 4 : Expand the identified object in the object structure
Step 5 : Populate Alternate Key field with the index noted in step 1 and save

Steps to enable alternate key in object :

Step 1 : Note down the desired index name for the object from Database Configuration application (Indexes Tab)
Step 2 : Navigate to System Configuration -> Platform Configuration -> Database Configuration
Step 3 : Select the object you wish to enable the alternate key 
Step 4 : Populate Alternate Index field with the index noted in step 1 and save

Expected Result:
Alternate key/index will be set for the object structure or object as per the above performed configuration steps.

Key Benefit :
This feature helps to identify records using different field combination other than the fields of default/primary index of the object.