issue: #43072, #43289
- manage the schema version at recovery storage.
- update the schema when creating collection or alter schema.
- get schema at write buffer based on version.
- recover the schema when upgrading from 2.5.
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Signed-off-by: chyezh <chyezh@outlook.com>
Iterators are long deprecated, but sort are still using it. This PR
unifies stats task with the latest compaction common functions and
remove the usage of iterators.
1. Rename `datanode/compaction` to `datanode/compactor`
2. Add `internal/compaction` and move some compaction commons into it.
3. Replace `DeltalogIterators` with `ComposeDeleteFromDeltalogs`
4. Remove `datanode/iterators`
See also: #39242
Signed-off-by: yangxuan <xuan.yang@zilliz.com>
