Some thoughts on generic keys

[XiangpengHao]

Current generic key support in Congee is broken: every key type is stored as usize and compared as usize. The ordering of the original generic key is ignored.
ART is a radix tree and implicitly assumes keys to be strings. It supports integer numbers because it happens to have a meaningful byte-order (depending on the endian).

Therefore only two types of keys are meaningful to Congee: string and integer numbers. In fact, production database may only support string keys as the index (e.g., BigTable).
In the future, Congee will only support string. Support for integer numbers will be a syntax sugar.