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TiDB 3.0.8 Release Notes
Release date: December 31, 2019
TiDB version: 3.0.8
TiDB Ansible version: 3.0.8
TiDB
- SQL Optimizer
- Fix the wrong SQL binding plan caused by untimely cache updates #13891
- Fix the issue that the SQL binding might be invalid when an SQL statement contains a symbol list #14004
- Fix the issue that an SQL binding cannot be created or deleted because an SQL statement ends with
;
#14113 - Fix the issue that a wrong SQL query plan might be selected because the
PhysicalUnionScan
operator sets wrong statistics #14133 - Remove the
minAutoAnalyzeRatio
restriction to makeautoAnalyze
more timely #14015
- SQL Execution Engine
- Fix issues that the
INSERT/REPLACE/UPDATE ... SET ... = DEFAULT
syntax might report an error and combining the usage of theDEFAULT
expression with a virtual generated column might report an error #13682 - Fix the issue that the
INSERT
statement might report an error when converting a string to a float #14011 - Fix the issue that sometimes the aggregate operation is low effective because the concurrency value of the
HashAgg
executor is incorrectly initialized #13811 - Fix the issue that an error is reported in the execution of
group by item
when the clause is in the parentheses #13658 - Fix the issue that the execution of
OUTER JOIN
might report an error because TiDB incorrectly calculatesgroup by item
#14014 - Fix the issue that the error message is inaccurate when Range-exceeding data is written into Range partitioned tables #14107
- Revert PR #10124 and cancel the
PadCharToFullLength
effect to avoid unexpected query results in special cases, considering that MySQL 8 will discardPadCharToFullLength
soon #14157 - Fix the goroutine leak issue when executing the
EXPLAIN ANALYZE
statement caused by unguaranteedclose()
calling inExplainExec
#14226
- Fix issues that the
- DDL
- Optimize the error message output of
change column
/modify column
to make it easier to understand #13796 - Add the
SPLIT PARTITION TABLE
syntax to support splitting Regions for partitioned tables #13929 - Fix the issue that the index length exceeds 3072 bytes and no error is reported because the index length is incorrectly checked when an index is created #13779
- Fix the issue that the
GC life time is shorter than transaction duration
error message might be reported because it takes too much time to add an index in partitioned tables #14132 - Fix the panic when
SELECT * FROM information_schema.KEY_COLUMN_USAGE
is executed because the foreign key is not checked whenDROP COLUMN
/MODIFY COLUMN
/CHANGE COLUMN
is executed #14105
- Optimize the error message output of
- Server
- Statement Summary improvements:
- Add a large number of SQL metric fields to facilitate analyzing SQL statements in more detail #14151, #14168
- Add the
stmt-summary.refresh-interval
parameter to control whether to move the stale data from theevents_statements_summary_by_digest
table to theevents_statements_summary_by_digest_history
table (the default interval: 30 minutes) #14161 - Add the
events_statements_summary_by_digest_history
table to save the stale data inevents_statements_summary_by_digest
#14166
- Fix the issue that the binlog is incorrectly output when RBAC-related internal SQL statements are executed #13890
- Add the
server-version
configuration item to control the feature of modifying the TiDB server version #13906 - Add the feature of using the HTTP interface to recover writing the TiDB binlog #13892
- Update the privilege required by
GRANT roles TO user
fromGrantPriv
toROLE_ADMIN
orSUPER
, to keep consistency with the MySQL behavior #13932 - Modify the TiDB behavior from using the current database to reporting the
No database selected
error when theGRANT
statement does not specify a database name, to keep compatibility with the MySQL behavior #13784 - Modify the execution privilege for the
REVOKE
statement fromSuperPriv
toREVOKE
being executable only if the user has the privilege for the corresponding schema, to keep consistency with the MySQL behavior #13306 - Fix the issue that
GrantPriv
is mistakenly granted to the target user when theGRANT ALL
syntax does not containWITH GRANT OPTION
#13943 - Fix the issue that the error message does not contain the cause for the
LOAD DATA
statement’s wrong behavior whenLoadDataInfo
fails to calladdRecord
#13980 - Fix the issue that wrong slow query information is output because multiple SQL statements in a query share the same
StartTime
#13898 - Fix the issue that the memory might leak when
batchClient
processes a large transaction #14032 - Fix the issue that
system_time_zone
is always displayed asCST
and now TiDB’ssystem_time_zone
is obtained fromsystemTZ
in themysql.tidb
table #14086 - Fix the issue that the
GRANT ALL
syntax does not grant all privileges to the user #14092 - Fix the issue that the
Priv_create_user
privilege is invalid forCREATE ROLE
andDROP ROLE
#14088 - Modify the error code of
ErrInvalidFieldSize
from1105(Unknow Error)
to3013
#13737 - Add the
SHUTDOWN
command to stop a TiDB server and add theShutdownPriv
privilege #14104 - Fix the atomicity issue for the
DROP ROLE
statement to avoid some roles being deleted unexpectedly when TiDB fails to execute a statement #14130 - Fix the issue that the
tidb_enable_window_function
in theSHOW VARIABLE
result incorrectly outputs1
when a TiDB version is upgraded to 3.0, and replace the wrong result with0
#14131 - Fix the issue that the goroutine might leak because
gcworker
continuously retries when the TiKV node is offline #14106 - Record the binlog
Prewrite
time in the slow query log to improve the usability for issue tracking #14138 - Make the
tidb_enable_table_partition
variable supportGLOBAL SCOPE
#14091 - Fix the issue that the user privilege might be missing or mistakenly added because the newly added privilege is not correctly granted to the corresponding user when a new privilege is added #14178
- Fix the issue that the
CheckStreamTimeoutLoop
goroutine might leak becauserpcClient
does not close when the TiKV server is disconnected #14227 - Support certificate-based authentication (User document) #13955
- Statement Summary improvements:
- Transaction
- Update the default value of the
tidb_txn_mode
variable from""
to"pessimistic"
when a new cluster is created #14171 - Fix the issue that the lock waiting time is too long for a pessimistic transaction because the lock waiting time for a single statement is not reset when a transaction is retried #13990
- Fix the issue that wrong data might be read because unmodified data is unlocked for the pessimistic transaction mode #14050
- Fix repeated insert value restriction checks because transaction types are not distinguished when prewrite is performed in mocktikv #14175
- Fix the panic because transactions are not correctly handled when
session.TxnState
isInvalid
#13988 - Fix the issue that the
ErrConfclit
structure in mocktikv does not containConflictCommitTS
#14080 - Fix the issue that the transaction is blocked because TiDB does not correctly check lock timeout after resolving the lock #14083
- Update the default value of the
- Monitor
- Add the
pessimistic_lock_keys_duration
monitoring item inLockKeys
#14194
- Add the
TiKV
- Coprocessor
- Raftstore
- Engine
- Fix the issue that empty data might be returned because RocksDB iterator errors are not correctly processed in extreme conditions #6326
- Transaction
- Update the default value of
tikv_alloc
fromtikv_alloc/default
tojemalloc
#6206
PD
- Client
- Optimize the performance for the
/api/v1/regions
API #1986 - Fix the issue that deleting stores in a
tombstone
state might cause a panic #2038 - Fix the issue that overlapped Regions are mistakenly deleted when loading the Region information from disks #2011, #2040
- Upgrade etcd from v3.4.0 to v3.4.3 (note that after upgrading you can only degrade etcd using pd-recover) #2058
Tools
- TiDB Binlog
- Fix the issue that the binlog is ignored because Pump does not receive the DDL committed binlog #853
TiDB Ansible
- Revert the simplified configuration item #1053
- Optimize the logic for checking the TiDB version when performing a rolling update #1056
- Upgrade TiSpark to v2.1.8 #1061
- Fix the issue that the PD role monitoring item is wrongly displayed on Grafana #1065
- Optimize
Thread Voluntary Context Switches
andThread Nonvoluntary Context Switches
monitoring items on the TiKV Detail page on Grafana #1071
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