TiDB 2.0.4 Release Notes
On June 15, 2018, TiDB 2.0.4 is released. Compared with TiDB 2.0.3, this release has great improvement in system compatibility and stability.
TiDB
- Support the
ALTER TABLE t DROP COLUMN a CASCADEsyntax - Support configuring the value of
tidb_snapshotto TSO - Refine the display of statement types in monitoring items
- Optimize the accuracy of query cost estimation
- Configure the
backoff max delayparameter of gRPC - Support configuring the memory threshold of a single statement in the configuration file
- Refactor the error of Optimizer
- Fix the side effects of the
Cast Decimaldata - Fix the wrong result issue of the
Merge Joinoperator in specific scenarios - Fix the issue of converting the Null object to String
- Fix the issue of casting the JSON type of data to the JSON type
- Fix the issue that the result order is not consistent with MySQL in the condition of
Union+OrderBy - Fix the compliance rules issue when the
Unionstatement checks theLimit/OrderByclause - Fix the compatibility issue of the
Union Allresult - Fix a bug in predicate pushdown
- Fix the compatibility issue of the
Unionstatement with theFor Updateclause - Fix the issue that the
concat_wsfunction mistakenly truncates the result
PD
- Improve the behavior of the unset scheduling argument
max-pending-peer-countby changing it to no limit for the maximum number ofPendingPeers
TiKV
- Add the RocksDB
PerfContextinterface for debugging - Remove the
import-modeparameter - Add the
region-propertiescommand fortikv-ctl - Fix the issue that
reverse-seekis slow when many RocksDB tombstones exist - Fix the crash issue caused by
do_sub - Make GC record the log when GC encounters many versions of data