btree simple

[jxieeducation]

Here's a simple BTree implementation that I modified based on Teepark's BTree.

Current flaws with the BTree:

1. cannot do {key, value} search yet
2. not sure if the remove method should do nothing if an item is not in list OR raise an exception
3. no short way of converting a btree from one order to another

However, I think we can build on this to implement the backend index.

[adewes]

Hey @jxieeducation thanks for the pull request, this looks promising! Sorry that I didn't reply faster, I'm really busy right now but will have a detailed look at your code until next week. Thanks for your contribution :)

[adewes]

Hey Jason, sorry for taking so much time to review this, I was really busy this months. So this looks much more promising than the other BTree implementation! I think what we need now is an implementation that supports the following methods implemented in blitzdb.backends.file.index.Index:

• add_key(attributes,store_key) : Adds a store_key to the index, using attributes to index it.
• remove_key(store_key): Removes a store_key.
• get_keys_for(value): Retrieves all keys for a given attribute value.
• sort_keys(keys,order = 1): Sorts a list of keys in a given order.

Let me know if you have any questions, I think your example goes in the right direction. It will probably a good idea to write tests for the Index class as well so that we have a test suite we can develop against.

[adewes]

Hey @jxieeducation , I will close this PR for now, let me know if you have time to contribute to BlitzDB again, your help is highly appreciated :)