[polskibus]

Would you mind comparing TiDB to other HTAP databases like SAP HANA, MemSQL, HyPer? I'm more interested in the architecture, trade-offs, best/worst use cases. How would you compare the analytical bit with regard to analytical databases like ClickHouse, SQL Server tabular model, MapD?

[morgo]

At a high level:

- TiDB is Open Source (Apache 2.0 license). Several others that you mention here are commercial offerings.

- The expected data volume for TiDB is larger than memory. I believe MemSQL, for example, is memory-only.

- The architecture of TiDB is inspired by Google Spanner.

- We try to be transparent on less-suited cases. See large+small transactions, single-threaded workloads from: https://www.pingcap.com/docs/sql/mysql-compatibility/

In regards to the analytical piece:

- We suggest you use TiDB for "adhoc OLAP", and Spark for more complicated cases. While parallel, the data is still stored in a row-format (more on that next year!), so an OLAP-only solution may still have performance advantages. TiDB also supports hash joins/aggregation/sort merge joins etc. So compared to MySQL for example, you should see quite a performance improvement.

Hope this helps!

[polskibus]

Thanks for the info. As far as I know other HTAPs often use row storage and column storage together, moving data from row to column over time. It seems like lack of such structure could be a drawback for TiDB in comparison to others.

[gregwebs]

Yes, that's correct. Expect more development on this front soon.