{
  "summary": [
    {
      "name": "world_snapshot",
      "title": "世界状态快照表",
      "primary": ["id"],
      "catelog": "entity"
    }
  ],
  "fields": [
    {"name": "id", "title": "主键ID", "type": "str", "length": 32, "nullable": "no"},
    {"name": "world_id", "title": "世界ID", "type": "str", "length": 32, "nullable": "no"},
    {"name": "name", "title": "快照名称", "type": "str", "length": 255, "nullable": "no"},
    {"name": "snapshot_type", "title": "快照类型", "type": "str", "length": 32, "nullable": "no", "default": "full"},
    {"name": "snapshot_json", "title": "快照内容JSON", "type": "text"},
    {"name": "checksum", "title": "快照校验和(sha256)", "type": "str", "length": 64},
    {"name": "version", "title": "快照版本", "type": "int", "length": 11, "nullable": "no", "default": "1"},
    {"name": "status", "title": "快照状态", "type": "str", "length": 32, "nullable": "no", "default": "active"},
    {"name": "snapshot_date", "title": "快照日期", "type": "timestamp", "nullable": "no"},
    {"name": "created_at", "title": "创建时间", "type": "timestamp", "nullable": "no"},
    {"name": "updated_at", "title": "更新时间", "type": "timestamp", "nullable": "no"}
  ],
  "indexes": [
    {"name": "idx_snap_world_list", "idxtype": "index", "idxfields": ["world_id", "created_at"]},
    {"name": "idx_snap_status_type", "idxtype": "index", "idxfields": ["status", "snapshot_type"]},
    {"name": "uk_snap_world_version", "idxtype": "unique", "idxfields": ["world_id", "version"]}
  ],
  "codes": [
    {"field": "snapshot_type", "table": "appcodes_kv", "valuefield": "k", "textfield": "v", "cond": "parentid='snapshot_type'"},
    {"field": "status", "table": "appcodes_kv", "valuefield": "k", "textfield": "v", "cond": "parentid='snapshot_status'"}
  ]
}