TiDB 5.4.1 Release Notes
Release Date: May 13, 2022
TiDB version: 5.4.1
Compatibility changes
TiDB v5.4.1 does not introduce any compatibility changes in product design. But note that bug fixes in this release might result in compatibility changes, too. For more information, see Bug Fixes.
Improvements
TiDB
- Support using the PointGet plan for queries that read the
_tidb_rowid
column #31543 - Add more logs and metrics for the
Apply
operator to show whether it is parallel #33887 - Improve the
TopN
pruning logic for Analyze Version 2 used for collecting statistics #34256 - Support displaying multiple Kubernetes clusters in the Grafana dashboard #32593
- Support using the PointGet plan for queries that read the
TiKV
- Support displaying multiple Kubernetes clusters in the Grafana dashboard #12104
PD
- Support displaying multiple Kubernetes clusters in the Grafana dashboard #4673
TiFlash
- Support displaying multiple Kubernetes clusters in the Grafana dashboard #4129
Tools
TiCDC
TiDB Data Migration (DM)
- Support Syncer using the working directory of the DM-worker rather than
/tmp
to write internal files, and cleaning the directory after the task is stopped #4107
- Support Syncer using the working directory of the DM-worker rather than
Bug Fixes
TiDB
- Fix the issue that
date_format
in TiDB handles'\n'
in a MySQL-incompatible way #32232 - Fix the issue that TiDB writes wrong data due to the wrong encoding of the
ENUM
orSET
column #32302 - Fix the issue that the Merge Join operator gets wrong results in certain cases #33042
- Fix the issue that TiDB gets a wrong result when a correlated subquery returns a constant #32089
- Fix the issue that TiDB gets the wrong result when using TiFlash to scan tables with empty range although TiFlash does not support reading tables with empty range yet #33083
- Fix the issue that the
MAX
orMIN
function on theENUM
orSET
column returns a wrong result when the new collation is enabled in TiDB #31638 - Fix a bug that CTE might be blocked when a query reports errors #31302
- Fix wrong range calculation results for Nulleq function on Enum values #32428
- Fix TiDB OOM when exporting data using ChunkRPC #31981 #30880
- Fix a bug that
tidb_super_read_only
is not automatically enabled whentidb_restricted_read_only
is enabled #31745 - Fix the issue that the
greatest
orleast
function with collation gets a wrong result #31789 - Fix load data panic if the data is broken at an escape character #31589
- Fix the
invalid transaction
error when executing a query using index lookup join #30468 - Fix wrong results of deleting data of multiple tables using
left join
#31321 - Fix a bug that TiDB may dispatch duplicate tasks to TiFlash #32814
- Fix the issue that granting the
all
privilege might fail in clusters that are upgraded from v4.0 #33588 - Fix the session panic that occurs when executing the prepared statement after table schema change with the MySQL binary protocol #33509
- Fix the issue that executing SQL statements that have the
compress()
expression withtidb_enable_vectorized_expression
enabled will fail #33397 - Fix the issue of high CPU usage by the
reArrangeFallback
function #30353 - Fix the issue that the table attributes are not indexed when a new partition is added and the issue that the table range information is not updated when the partition changes #33929
- Fix a bug that the
TopN
statistical information of a table during the initialization is not correctly sorted #34216 - Fix the error that occurs when reading from the
INFORMATION_SCHEMA.ATTRIBUTES
table by skipping the unidentifiable table attributes #33665 - Fix a bug that even if
@@tidb_enable_parallel_apply
is set, theApply
operator is not paralleled when anorder
property exists #34237 - Fix a bug that
'0000-00-00 00:00:00'
can be inserted into adatetime
column whensql_mode
is set toNO_ZERO_DATE
#34099 - Fix the issue that the TiDB server might run out of memory when the
INFORMATION_SCHEMA.CLUSTER_SLOW_QUERY
table is queried. This issue can be triggered when you check slow queries on the Grafana dashboard #33893 - Fix a bug that in the
NOWAIT
statement, a transaction being executed does not return immediately when encountering a lock #32754 - Fix a bug that causes a failure when creating a table with the
GBK
charset andgbk_bin
collation #31308 - Fix a bug that when
enable-new-charset
ison
, creating aGBK
charset table with collation fails with the "Unknown character set" error #31297
- Fix the issue that
TiKV
- Fix the issue that TiKV panics and destroys peers unexpectedly because the target Region to be merged is invalid #12232
- Fix a bug that stale messages cause TiKV to panic #12023
- Fix the issue of intermittent packet loss and out of memory (OOM) caused by the overflow of memory metrics #12160
- Fix the potential panic issue that occurs when TiKV performs profiling on Ubuntu 18.04 #9765
- Fix a bug that replica reads might violate the linearizability #12109
- Fix the TiKV panic issue that occurs when the target peer is replaced with the peer that is destroyed without being initialized when merging a Region #12048
- Fix a bug that TiKV might panic if it has been running for 2 years or more #11940
- Reduce the TiCDC recovery time by reducing the number of the Regions that require the Resolve Locks step #11993
- Fix the panic issue caused by deleting snapshot files when the peer status is
Applying
#11746 - Fix the issue that destroying a peer might cause high latency #10210
- Fix the panic issue caused by invalid assertion in resource metering #12234
- Fix the issue that slow score calculation is inaccurate in some corner cases #12254
- Fix the OOM issue caused by the
resolved_ts
module and add more metrics #12159 - Fix the issue that successfully committed optimistic transactions may report the
Write Conflict
error when the network is poor #34066 - Fix the TiKV panic issue that occurs when replica read is enabled on a poor network #12046
PD
- Fix the issue that
Duration
fields ofdr-autosync
cannot be dynamically configured #4651 - Fix the issue that when there exists a Store with large capacity (2T for example), fully allocated small Stores cannot be detected, which results in no balance operator being generated #4805
- Fix the issue that the label distribution has residual labels in the metrics #4825
- Fix the issue that
TiFlash
- Fix the panic issue that occurs when TLS is enabled #4196
- Fix possible metadata corruption caused by Region merge on a lagging Region peer #4437
- Fix the issue that a query containing
JOIN
might be hung if an error occurs #4195 - Fix a bug that MPP tasks might leak threads forever #4238
- Fix the overflow that occurs when casting
FLOAT
toDECIMAL
#3998 - Fix the issue that expired data is recycled slowly #4146
- Fix a bug that canceled MPP queries might cause tasks to hang forever when the local tunnel is enabled #4229
- Fix the issue of memory leak that occurs when a query is canceled #4098
- Fix the wrong result that occurs when casting
DATETIME
toDECIMAL
#4151 - Fix the potential issue of TiFlash panic when
Snapshot
is applied simultaneously with multiple DDL operations #4072 - Fix the bug that invalid storage directory configurations lead to unexpected behaviors #4093
- Fix the bug that some exceptions are not handled properly #4101
- Fix the issue that casting
INT
toDECIMAL
might cause overflow #3920 - Fix the issue that the result of
IN
is incorrect in multi-value expressions #4016 - Fix the issue that the date format identifies
'\n'
as an invalid separator #4036 - Fix the potential query error after adding columns under heavy read workload #3967
- Fix the panic issue that occurs when the memory limit is enabled #3902
- Fix potential data corruption in DTFiles #4778
- Fix potential errors when querying on a table with many delete operations #4747
- Fix a bug that TiFlash reports many "Keepalive watchdog fired" errors randomly #4192
- Fix a bug that data not matching any region range remains on a TiFlash node #4414
- Fix a bug that empty segments cannot be merged after GC #4511
Tools
Backup & Restore (BR)
- Fix a bug that causes the restore operation to fail when the encryption information is lost during backup retry #32423
- Fix the issue that BR fails to back up RawKV #32607
- Fix duplicate primary keys when inserting a record into a table after incremental restoration #33596
- Fix a bug that BR incremental restore returns errors mistakenly due to DDL jobs with empty query #33322
- Fix the potential issue that Regions might be unevenly distributed after a restore operation is finished #31034
- Fix the issue that BR does not retry enough times when Regions are not consistent during restoration #33419
- Fix the issue that BR might panic occasionally when merging small files is enabled #33801
- Fix the issue that schedulers do not resume after BR or TiDB Lightning exits abnormally #33546
TiCDC
- Fix incorrect metrics caused by owner changes #4774
- Fix the TiCDC panic issue that might occur because
Canal-JSON
does not support nil #4736 - Fix a stability problem in workerpool used by Unified Sorter #4447
- Fix a bug that sequence is incorrectly replicated in some cases #4552
- Fix the TiCDC panic issue that might occur when
Canal-JSON
incorrectly handlesstring
#4635 - Fix a bug that a TiCDC node exits abnormally when a PD leader is killed #4248
- Fix a bug that MySQL sink generates duplicated
replace
SQL statements whenbatch-replace-enable
is disabled #4501 - Fix the DML construct error caused by the
rename tables
DDL #5059 - Fix the issue that in rare cases replication can be stuck if the owner is changed and the new scheduler is enabled (disabled by default) #4963
- Fix the issue that the error ErrProcessorDuplicateOperations is reported when the new scheduler is enabled (disabled by default) #4769
- Fix the issue that TiCDC fails to start when the first PD set in
--pd
is not available after TLS is enabled #4777 - Fix the issue that the checkpoint metrics are missing when tables are being scheduled #4714
TiDB Lightning
- Fix the checksum error "GC life time is shorter than transaction duration" #32733
- Fix the issue that TiDB Lightning gets stuck when it fails to check empty tables #31797
- Fix a bug that TiDB Lightning may not delete the metadata schema when some import tasks do not contain source files #28144
- Fix the issue that the precheck does not check local disk resources and cluster availability #34213
TiDB Data Migration (DM)
- Fix the issue that hundreds of "checkpoint has no change, skip sync flush checkpoint" print in the log and the replication is very slow #4619
- Fix a bug that long varchars report an error
Column length too big
#4637 - Fix the issue that execution errors of the update statement in safemode may cause the DM-worker panic #4317
- Fix the issue that in some cases manually executing the filtered DDL in the downstream might cause task resumption failure #5272
- Fix a bug that no data is returned for the
query-status
command when binlog is not enabled in the upstream #5121 - Fix the DM worker panic issue that occurs when the primary key is not first in the index returned by the
SHOW CREATE TABLE
statement #5159 - Fix the issue that CPU usage may increase and a large amount of log is printed when GTID is enabled or when the task is automatically resumed #5063