Redis データモデリング Redis Core

Recommendation

Profile cache: use a Hash per user. Leaderboard: use a Sorted Set per board.

User profile: Hash

The JSON string forces fetch, parse, mutate and rewrite for every change. A Hash lets you touch one field at a time:

HSET user:1001:profile name "Ada" email "[email protected]" level 42 country "DE"

HSET  user:1001:profile email "[email protected]"   # update one field, no read needed
HGET  user:1001:profile email                      # read one field
HGETALL user:1001:profile                          # read everything
HINCRBY user:1001:profile level 1                  # atomic numeric update
EXPIRE user:1001:profile 3600                      # TTL, since this is a cache

This is atomic, needs no read-modify-write cycle, and avoids lost updates when two writers race. It also sends far less data over the wire.

Hashes hold flat field/value pairs. If the profile has nested data, such as arrays of items or sub-objects, use the JSON type (JSON.SET user:1001:profile $.address.city '"Berlin"'). Otherwise a Hash is simpler and lighter. You can also keep rarely changed nested parts in a separate key, for example user:1001:settings.

Leaderboard: Sorted Set

ZADD   game:space-invaders:leaderboard 12500 user:1001   # set/update score
ZINCRBY game:space-invaders:leaderboard 300 user:1001     # add points atomically
ZREVRANGE game:space-invaders:leaderboard 0 9 WITHSCORES  # top 10
ZREVRANK  game:space-invaders:leaderboard user:1001       # a player's rank

The member should be the user ID, not the whole profile. To render the board, take the top N IDs and fetch each profile with HMGET or HGETALL, pipelined.

Key naming

Use lowercase, colon-separated keys in the form {entity}:{id}:{attribute}. User_1001_Profile breaks that convention in casing, separators and order.

Further tips:

• Keep keys short, because they live in memory and appear in every command.
• Pick one convention and apply it everywhere.
• If you're multi-tenant, prefix with the tenant (tenant:42:user:1001:profile). That makes scans and ACLs easy to scope.
• Time-bucketed leaderboard keys such as weekly or daily boards can be expired or rotated with EXPIRE.

Migration

1. Write a one-off script that reads each User_*_Profile string, parses it and does HSET user:{id}:profile ....
2. Have the app write to the new keys, or dual-write briefly.
3. Delete the old keys once reads are fully switched over. Use SCAN for this, never KEYS.

I can sketch the migration script or the client code in Python or Java if that would help.