releases: add TiDB 4.0.5 release notes

TOC.md

@@ -508,6 +508,7 @@
 + Release Notes
   + [All Releases](/releases/release-notes.md)
   + v4.0
+    + [4.0.5](/releases/release-4.0.5.md)
     + [4.0.4](/releases/release-4.0.4.md)
     + [4.0.3](/releases/release-4.0.3.md)
     + [4.0.2](/releases/release-4.0.2.md)

releases/release-4.0.5.md

@@ -0,0 +1,95 @@
+---
+title: TiDB 4.0.5 Release Notes
+---
+
+# TiDB 4.0.5 Release Notes
+
+Release date: August 10, 2020
+
+TiDB version: 4.0.5
+
+## Compatibility Changes
+
++ TiDB
+
+    - Change drop partition and truncate partition's job args to support multi partition id array [#18930](https://github.com/pingcap/tidb/pull/18930)
+    - Add delete only state for add partition replica check [#18865](https://github.com/pingcap/tidb/pull/18865)
+
+## New Features
+
++ TiFlash
+
+    - Support standard error code [#978](https://github.com/pingcap/tics/pull/978)
+
++ TiKV
+
+     - Define error code for errors [#8387](https://github.com/tikv/tikv/pull/8387)
+
+## Improvements
+
++ TiDB
+
+    - Optimize the performance of decodePlan for big union query [#18941](https://github.com/pingcap/tidb/pull/18941)
+    - Reduce GC scan locks when meeting region cache miss [#18876](https://github.com/pingcap/tidb/pull/18876)
+    - Ease the impact of stats feedback on cluster [#18772](https://github.com/pingcap/tidb/pull/18772)
+    - Support cancel before RPC response return. [#18580](https://github.com/pingcap/tidb/pull/18580)
+    - Add HTTP API to generate TiDB metric profile. [#18531](https://github.com/pingcap/tidb/pull/18531)
+    - Fix the partition table issue in table scatter API. [#17863](https://github.com/pingcap/tidb/pull/17863)
+    - Add detailed memory usage for each instance in grafana.
+    - Add runtime information for the batch-point-get executor [#18892](https://github.com/pingcap/tidb/pull/18892)
+    - Add executor runtime information for point-get. [#18817](https://github.com/pingcap/tidb/pull/18817)
+    - Warn potential deadlock for Consume in remove [#18395](https://github.com/pingcap/tidb/pull/18395)
+
++ PD
+
+    - Support scattering regions in stores with special engines (like TiFlash). [#2706](https://github.com/pingcap/pd/pull/2706)
+    - Support Region HTTP API to promote regions schedule by given key range. [#2687](https://github.com/pingcap/pd/pull/2687)
+    - Improve the leader distribution after region scatter. [#2684](https://github.com/pingcap/pd/pull/2684)
+    - Add more tests and logs for TSO request. [#2678](https://github.com/pingcap/pd/pull/2678)
+    - Avoid invalid cache updates after the leader of a region has changed. [#2672](https://github.com/pingcap/pd/pull/2672)
+
++ TiFlash
+
+    - Feature: support unified log format [#977](https://github.com/pingcap/tics/pull/977)
+    - Add some panels about IO operations on Grafana [#965](https://github.com/pingcap/tics/pull/965)
+    - Optimize `IngestSst` by reducing persisting uncommitted region data. [#960](https://github.com/pingcap/tics/pull/960)
+    - Accelerate regions schedule for blocked add partition ddl [#959](https://github.com/pingcap/tics/pull/959)
+    - Optimize the process of DeltaTree's delta data compaction to reduce unnecessary read and write amplification [#952](https://github.com/pingcap/tics/pull/952)
+    - Optimize applying snapshot by preprocessing under multi-thread. [#944](https://github.com/pingcap/tics/pull/944)
+
+## Bug Fixes
+
++ TiDB
+
+    - Check ErrTruncate/Overflow locally for builtinCastRealAsDecimalSig to fix the "should ensure all columns have the same length" error [#18967](https://github.com/pingcap/tidb/pull/18967)
+    - Fix a encode bug causes the wrong result of hashJoin with set and enum [#18859](https://github.com/pingcap/tidb/pull/18859)
+    - Fix issue `pre_split_regions` table option doesn't work in the partition table. [#18837](https://github.com/pingcap/tidb/pull/18837)
+    - Fixed an issue that could cause a large transaction to be terminated prematurely. [#18813](https://github.com/pingcap/tidb/pull/18813)
+    - Fix incorrect collator when `getSignatureByPB` and remove unnecessary recover [#18735](https://github.com/pingcap/tidb/pull/18735)
+    - Fix a bug `getAutoIncrementID()` function does not consider the `tidb_snapshot` session variable, this bug may cause dumper tool fail with 'table not exist' error. [#18692](https://github.com/pingcap/tidb/pull/18692)
+    - Fix unknown column error for sql like `select a from t having t.a` [#18434](https://github.com/pingcap/tidb/pull/18434)
+    - Support the Action when memory exceed quota for TableReader Executor. [#18392](https://github.com/pingcap/tidb/pull/18392)
+    - Fix a panic on hash partition table when the query condition is that the partition column equals to a big number like 9223372036854775808 [#18186](https://github.com/pingcap/tidb/pull/18186)
+    - Refine the behavior of StrToInt and StrToFloat and support convert JSON to date, time and timestamp [#18159](https://github.com/pingcap/tidb/pull/18159)
+    - Fix the wrong behavior of char function. [#18122](https://github.com/pingcap/tidb/pull/18122)
+    - Ddl: fix admin repair table with range partition expr will parseInt fail [#17988](https://github.com/pingcap/tidb/pull/17988)
+    - Fix wrong behavior of set charset statement [#17289](https://github.com/pingcap/tidb/pull/17289)
+    - Fix a bug caused by the wrong collation setting which leads to the wrong result of collation function. [#17231](https://github.com/pingcap/tidb/pull/17231)
+    - Fix STR_TO_DATE's handling for format token '%r', '%h' [#18727](https://github.com/pingcap/tidb/pull/18727)
+    - Fix issues of TiDB version information formation doesn't consistent with PD/TiKV in cluster_info table. [#18413](https://github.com/pingcap/tidb/pull/18413)
+
++ PD
+
+    - Fix the bug that TSO request may fail at the time of leader changing. [#2666](https://github.com/pingcap/pd/pull/2666)
+    - Fix the issue that when enabling placement rules, sometimes region replicas cannot schedule to optimal [#2720](https://github.com/pingcap/pd/pull/2720)
+
+
++ TiFlash
+
+    - Fix the issue that TiFlash cannot start normally after upgrading from an old version if the name of the database or table contains special characters. [#971](https://github.com/pingcap/tics/pull/971)
+    - Fix bug: tiflash can not exit if any exception is thrown during initialization [#953](https://github.com/pingcap/tics/pull/953)
+
++ TiKV
+
+    - Fix memory leak during scheduling [#8357](https://github.com/tikv/tikv/pull/8357)
+    - Speed up leader election when hibernate region is enabled [#8292](https://github.com/tikv/tikv/pull/8292)

releases/release-notes.md

@@ -7,6 +7,7 @@ aliases: ['/docs/dev/releases/release-notes/','/docs/dev/releases/rn/']
 
 ## 4.0
 
+- [4.0.5](/releases/release-4.0.5.md)
 - [4.0.4](/releases/release-4.0.4.md)
 - [4.0.3](/releases/release-4.0.3.md)
 - [4.0.2](/releases/release-4.0.2.md)