V2.3.2 Release Plan

[roseduan]

• #274

• #275

  • Ascend, Descend, etc.

• add a function to support iterating all keys

  • discussion: #265

• #270

  • we can add two functions:
    • Expire(key []byte): set expire time for a key
    • TTL(key []byte): get the ttl of the key

• #272