1. A system comprising: a database system implemented using a server system comprising one or more processors, the database system configurable to cause: processing a post shared by a user of an online social network in a feed of the online social network, the post comprising textual content and being identifiable through one or more objects stored in a database, the feed being displayable in a user interface on a display device, the processing of the post comprising: identifying a first keyword of the textual content of the post as being preceded by a first tag to define a first tagged keyword, identifying a first data source specified by the first tag, the first data source being external to the database system, identifying a second keyword of the textual content of the post as being preceded by the first tag or a second tag to define a second tagged keyword, and identifying a second data source specified by the first tag or the second tag, the second data source being different from the first data source and being external to the database system; requesting a first search of the first data source using the first keyword; requesting a second search of the second data source using the second keyword; and processing a plurality of content records identified by the searches, the processing of the content records comprising: selecting one or more of the content records as satisfying criteria specifying one or more of: a visibility of a content record, a relevance of a content record, a designated data source for a content record, a type of a content record, an action to perform in association with a content record, or a time range for an action to be performed in association with a content record, and responsive to selecting the one or more content records as satisfying the criteria, automatically generating and sharing in the feed a comment on the post, the comment comprising at least a portion of record content of the selected one or more content records; selecting a further content record in accordance with further criteria, the further criteria being configurable using a settings interface; automatically generating and sharing in the feed one or more further comments on the post, the one or more further comments comprising at least a portion of record content of the selected further content record; and automatically generating, using one or more heuristics, a feed tracked update associated with the selected further content record.