Weekly update in TiDB

Last week, we landed 41 PRs in the TiDB repositories.

Added

• Support the built-in function: str_to_date.

• Support built-in function schema().

• Support pushing the case-when expression to TiKV.

• Support changing the type and name of a column.

• Add the ](https://github.com/pingcap/tidb/pull/2194)[session_variables and plugins of memory table to infoschema.

• Make the union all operator run parallelly.

• Support explaining the union statement.

Fixed

• A bug that causes infinite loop.

• A bug in the on duplicate… statement when updating the primary key (PK)

• Make the charset name case-insensitive.

• Forbid dropping columns with the auto_inc and PK attribute.

• Fix bugs in the parser.

Improved

• Pass the filter to TiKV when scanning indexes.

• Allocate column/index IDs in the table space to make the IDs shorter.

Weekly update in TiKV

Last week, we landed 34 PRs in the TiKV repositories.

Added

• Support online backup of the RocksDB data for tikv-ctl debugging.

• Add replication constraints to schedule replicas.

• Support GrantLeaderScheduler to transfer all leaders to one store.

• Support ShuffleLeaderScheduler to shuffle leaders in different stores.

• Support Circle CI for TiKV and Placement Driver (PD).

• Add the state filter argument to get the stores API.

Fixed

• Use channel to fix the possible stale snapshot state, issue #1373.

• Report ServerIsBusy and let PD ignore the busy store when scheduling to fix #414.

Improved

• Speed up the shutdown duration to reduce the close waiting time.

• Add retry when initializing the cluster ID.

• Support safe ConfChange to fix #1366.

• Report pending peers to PD to improve its scheduler.

• Bind ports lazily to avoid the message channel full error when starting up.