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TiDB 4.0.0 Beta.1 Release Notes
Release date: February 28, 2020
TiDB version: 4.0.0-beta.1
TiDB Ansible version: 4.0.0-beta.1
Compatibility Changes
TiDB
- Modify the type of the
log.enable-slow-log
configuration item from integer to Boolean #14864 - Modify the
password
field name toauthentication_string
in themysql.user
system table to make it consistent with MySQL 5.7 (This compatibility change means that you cannot roll back to earlier versions.) #14598 - Adjust the default value of the
txn-total-size-limit
configuration item from1GB
to100MB
#14522 - Support dynamically modifying or updating configuration items read from PD #14750 #14303 #14830
- Modify the type of the
TiKV
PD
- Optimize the HTTP API to make it compatible with the configuration manager #2080
TiDB Lightning
- Use the default configurations specified in the document for certain items not configured in the configuration file #255
TiDB Ansible
New Features
TiDB
- Support querying slow logs of any time in the
SLOW_QUERY / CLUSTER_SLOW_QUERY
system table #14840 #14878 - Support SQL performance diagnosis
- Support the
Sequence
function #14731 #14589 #14674 #14442 #14303 #14830 - Support dynamically modifying or updating configuration items read from PD #14750 #14303 #14830
- Add a feature of automatically reading data from different roles according to the load balancing policy and add the
leader-and-follower
system variable to enable this feature #14761 - Add the
Coercibility
function #14739 - Support setting TiFlash replicas in the partitioned table #14735 #14713 #14644
- Improve the privilege check for the
SLOW_QUERY
table #14451 - Support automatically write the intermediate results to the disk file if the memory is insufficient when using a SQL join #14708 #14279
- Support checking table partitions by querying the
information_schema.PARTITIONS
system table #14347 - Add the
json_objectagg
aggregate function #11154 - Support logging rejected connection attempts in the audit log #14594
- Add the
max-server-connections
configuration item (4096
by default) to control the number of connections to a single server #14409 - Support the isolation read specifying multiple storage engines at the server level #14440
- Optimize the cost model of the
Apply
operator and theSort
operator to improve stability #13550 #14708
- Support querying slow logs of any time in the
TiKV
PD
- Support accessing to the distribution of hotspots in the cluster through Dashboard UI #2086
- Support capturing and displaying
START_TIME
andUPTIME
of cluster components #2116 - Add the information of deployment path and component version in the returned message of the
member
API #2130 - Add the
component
sub-command in pd-ctl to modify and check the configuration of other components (experimental) #2092
TiDB Binlog
TiDB Ansible
- Support deploying multiple Grafana/Prometheus/Alertmanagers in one cluster #1142
- Add the
metric_port
configuration item (8234
by default) in TiFlash's configuration file #1145 - Add the
flash_proxy_status_port
configuration item (20292
by default) in TiFlash's configuration file #1141 - Add the TiFlash monitoring dashboard #1147 #1151
Bug Fixes
TiDB
- Fix the issue that an error is reported when creating
view
with a column name that exceeds 64 characters #14850 - Fix the issue that duplicate data exists in
information_schema.views
because thecreate or replace view
statement is incorrectly processed #14832 - Fix the incorrect results of
BatchPointGet
whenplan cache
is enabled #14855 - Fix the issue that data is inserted into the wrong partitioned table after the timezone is modified #14370
- Fix the panic occurred when rebuilding expression using the invalid name of the
IsTrue
function during the outer join simplification #14515 - Fix the the incorrect privilege check for the
show binding
statement #14443
- Fix the issue that an error is reported when creating
TiKV
TiDB Lightning
- Fix the bug that the web interface does not work outside the Server mode #259
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