Is DeltaTree Index an Index?

This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: DeltaTree index是索引吗

| username: TiDBer_JlY1JCJ5

I see that there is a data structure called DeltaTree index in DeltaTree. Since this DeltaTree index is a data structure, isn’t it an index for TiFlash? TiFlash uses the Raft protocol to achieve data synchronization by reading the idx value of the Raft log for synchronization. Is there a specific document reference for this?

| username: come_true | Original post link

It looks like an index by the name :joy:

| username: 大飞哥online | Original post link

DeltaTree Index is a data structure in TiFlash used to merge the Stable layer and Delta layer during reads, providing an ordered data stream. DeltaTree Index acts similarly to an index in TiFlash, helping TiFlash quickly locate and merge data from the Stable layer and Delta layer during data reads.

| username: hey-hoho | Original post link

Here’s a reference that might help:

| username: dba远航 | Original post link

Training video 302 also covers this explanation.