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TiDB 4.0.16 Release Notes
Release date: December 17, 2021
TiDB version: 4.0.16
Compatibility changes
TiKV
- Before v4.0.16, when TiDB converts an illegal UTF-8 string to a Real type, an error is reported directly. Starting from v4.0.16, TiDB processes the conversion according to the legal UTF-8 prefix in the string #11466
Tools
Improvements
TiDB
- Upgrade the Grafana version from 7.5.7 to 7.5.11
TiKV
- Reduce disk space consumption by adopting the zstd algorithm to compress SST files when restoring data using Backup & Restore or importing data using Local-backend of TiDB Lightning #11469
Tools
Bug fixes
TiDB
- Fix the query panic caused by overflow in the statistics module when converting a range to points for cost estimation #23625
- Fix wrong results of the control functions (such as
IF
andCASE WHEN
) when using theENUM
type data as parameters of such functions #23114 - Fix the issue that the
GREATEST
function returns inconsistent results due to different values oftidb_enable_vectorized_expression
(on
oroff
) #29434 - Fix the panic when applying index join on prefix indexes in some cases #24547
- Fix the issue that planner might cache invalid plans for
join
in some cases #28087 - Fix a bug that TiDB cannot insert
null
into a non-null column whensql_mode
is empty #11648 - Fix the wrong result type of the
GREATEST
andLEAST
functions #29019 - Fix the
privilege check fail
error when performing thegrant
andrevoke
operations to grant and revoke global level privileges #29675 - Fix the panic when using the
CASE WHEN
function on theENUM
data type #29357 - Fix wrong results of the
microsecond
function in vectorized expressions #29244 - Fix wrong results of the
hour
function in vectorized expression #28643 - Fix the issue that optimistic transaction conflicts might cause transactions to block each other #11148
- Fix the issue of incomplete log information from the
auto analyze
result #29188 - Fix the issue that using an invalid default date does not report an error when the
SQL_MODE
is 'NO_ZERO_IN_DATE' #26766 - Fix the issue that the Coprocessor Cache panel in Grafana does not display metrics. Now, Grafana displays the number of
hits
/miss
/evict
#26338 - Fix the issue that concurrently truncating the same partition causes DDL statements to stuck #26229
- Fix the issue that the length information is wrong when converting
Decimal
toString
#29417 - Fix the issue of an extra column in the query result when
NATURAL JOIN
is used to join multiple tables #29481 - Fix the issue that
TopN
is wrongly pushed down toindexPlan
whenIndexScan
uses a prefix index #29711 - Fix the issue that retrying transactions with the auto-increment columns of
DOUBLE
type causes data corruption #29892
TiKV
- Fix a panic issue that occurs when Region merge, ConfChange, and Snapshot happen at the same time in extreme conditions #11475
- Fix the issue of negative sign when the decimal divide result is zero #29586
- Fix the issue that the average latency of the by-instance gRPC requests is inaccurate in TiKV metrics #11299
- Fix the issue of TiCDC panic that occurs when the downstream database is missing #11123
- Fix the issue that the Raft connection is broken when the channel is full #11047
- Fix the issue that TiDB cannot correctly identify whether the
Int64
types inMax
/Min
functions are a signed integer or not, which causes the wrong calculation result ofMax
/Min
#10158 - Fix the issue that CDC adds scan retries frequently due to the Congest error #11082
PD
TiFlash
- Fix the issue that TiFlash fails to start up on some platforms due to the absence of library
nsl
- Fix the issue that TiFlash fails to start up on some platforms due to the absence of library
Tools
TiDB Binlog
- Fix the bug that Drainer exits when transporting a transaction greater than 1 GB #28659
TiCDC
- Fix the negative value error in the changefeed checkpoint lag #3010
- Fix OOM in container environments #1798
- Fix the TiCDC replication interruption issue when multiple TiKVs crash or during a forced restart #3288
- Fix the memory leak issue after processing DDLs #3174
- Fix the issue that changefeed does not fail fast enough when the ErrGCTTLExceeded error occurs #3111
- Fix the issue that TiCDC replication task might terminate when the upstream TiDB instance unexpectedly exits #3061
- Fix the issue that TiCDC process might panic when TiKV sends duplicate requests to the same Region #2386
- Fix the issue that the volume of Kafka messages generated by TiCDC is not constrained by
max-message-size
#2962 - Fix the issue that
tikv_cdc_min_resolved_ts_no_change_for_1m
keeps alerting when there is no changefeed #11017 - Fix the issue that TiCDC sync task might pause when an error occurs during writing a Kafka message #2978
- Fix the issue that some partitioned tables without valid indexes might be ignored when
force-replicate
is enabled #2834 - Fix the memory leak issue when creating a new changefeed #2389
- Fix the issue that might cause inconsistent data due to Sink components advancing resolved ts early #3503
- Fix the issue that scanning stock data might fail due to TiKV performing GC when scanning stock data takes too long #2470
- Fix the issue that the changefeed update command does not recognize global command line parameters #2803
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