Systems and methods for automatically updating queries on a data store, such as a personal content database (PCDB), are provided. A query engine runs queries against two indexes: a first index that represents a previous state of documents and a second index that represents a current state of documents. The query is run twice and a delta analysis is performed, i.e., a determination is made as to which documents have changed in some respect from the previous state to the current state, and a view or a count associated with at least one query changes in accordance with the delta analysis. Transactions may be batched dynamically by a transaction manager until an optimal number of documents have changed or a certain amount of time has passed prior to re-running the query and performing the delta analysis.