Hi, >Why don't you simply keep the entire index in memory?
For specialized use cases this might work. In-memory repositories are nice, specially for testing. They are very fast. But for normal uses cases, this would be expensive. For a regular repository, one million nodes is not that much. Even 10 million nodes is not a lot depending on the use case. If we keep secondary indexes in the repository, the number of nodes will further increase. Even if the index is kept in memory, it still needs to be persisted once in a while. If you have an append-only storage, then you can afford only storing the index after x changes, because to re-build the index, you can use an old index and re-apply at most x-1 changes. But without append-only storage, re-building the index from the data takes time (linear to the size of the repository, or possibly linear to the size of the repository including old versions). Regards, Thomas
