A database structure and a system that uses the structure to facilitate efficient context enrichment of low-level events occurring in a distributed computing system. In one aspect, the database structure comprises a table accessible to a distributed storage system. The table comprises a plurality of rows. Each row represents a corresponding process creation event of a particular process at a particular host at a particular time and assigned a particular event identifier. Each row comprises a row key identifying the particular host, the particular process, the particular time, and the particular event identifier of the process creation event corresponding to the row. The particular time and the particular event identifier are stored as part of the row key in a bitwise one's complement format. The row key structure facilitates efficient identification of a process creation event where only hostname and the process identifier of the process creation event are known.