Disclosed are examples of systems, apparatus, methods and computer program products for generating or updating a graph of nodes and edges using logs, where the graph can be used for database searching. In some implementations, a server can identify logs. Based on the identified logs, log nodes can be generated or updated. Log nodes can be sorted in a first ordered list according to each log node's key data. Log node pairs can be determined from the log nodes in the first list. The log node pairs can be aggregated and sorted into a second ordered list. A graph of nodes and edges can be generated or updated according to the relative importances of the log node pairs in the second ordered list.