1. A method performed by a node in a set of nodes, the set of nodes implementing a distributed key-value store executed by one or more processors of the set of nodes, the method comprising: receiving, by the node, a search request from a user, the search request including a search expression and a target key namespace; selecting, by the node, one or more data log files from a plurality of data log files in response to the search request, wherein each data log file in the plurality of data log files stores key-value pairs for a key namespace of the distributed key-value store, and wherein the selected one or more data log files store key-value pairs for the target key namespace; searching, by the node, the selected one or more data log files for keys or key-value pairs that satisfy the search expression; and returning, by the node, the keys or key-value pairs to the user.