1ef7220f__Guide___Salesforce_Developers__Details
[Field] FeedPostId [Details] 
Type reference Properties Filter, Group, Nillable, Sort Description This field was removed in API version 22.0, and is available in earlier versions for backward compatibility only. ID of the associated FeedPost. A FeedPost represents the following types of changes in an FeedItem: changes to tracked fields, text posts, link posts, and content posts.
UserFeed | SOAP API Developer's Guide | Salesforce Developers
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