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TiDB 2.1.16 Release Notes
Release date: August 15, 2019
TiDB version: 2.1.16
TiDB Ansible version: 2.1.16
TiDB
- SQL Optimizer
- Fix the issue that row count is estimated inaccurately for the equal condition on the time column #11526
- Fix the issue that
TIDB_INLJ
Hint does not take effect or take effect on the specified table #11361 - Change the implementation of
NOT EXISTS
in a query from OUTER JOIN to ANTI JOIN to find a more optimized execution plan #11291 - Support subqueries within
SHOW
statements, allowing syntaxes such asSHOW COLUMNS FROM tbl WHERE FIELDS IN (SELECT 'a')
#11461 - Fix the issue that the
SELECT … CASE WHEN … ELSE NULL ...
query gets an incorrect result caused by the constant folding optimization #11441
- SQL Execution Engine
- Fix the issue that the
DATE_ADD
function gets a wrong result whenINTERVAL
is negative #11616 - Fix the issue that the
DATE_ADD
function might get an incorrect result because it performs type conversion wrongly when it accepts an argument of theFLOAT
,DOUBLE
, orDECIMAL
type #11628 - Fix the issue that the error message is inaccurate when CAST(JSON AS SIGNED) overflows #11562
- Fix the issue that other child nodes are not closed when one child node fails to be closed and returns an error during the process of closing Executor #11598
- Support
SPLIT TABLE
statements that return the number of Regions that are successfully split and a finished percentage rather than an error when the scheduling is not finished for Region scatter before the timeout #11487 - Make
REGEXP BINARY
function case sensitive to be compatible with MySQL #11505 - Fix the issue that
NULL
is not returned correctly because the value ofYEAR
in theDATE_ADD
/DATE_SUB
result overflows when it is smaller than 0 or larger than 65535 #11477 - Add in the slow query table a
Succ
field that indicates whether the execution succeeds #11412 - Fix the MySQL incompatibility issue caused by fetching the current timestamp multiple times when a SQL statement involves calculations of the current time (such as
CURRENT_TIMESTAMP
orNOW
) #11392 - Fix the issue that the AUTO_INCREMENT columns do not handle the FLOAT or DOUBLE type #11389
- Fix the issue that
NULL
is not returned correctly when theCONVERT_TZ
function accepts an invalid argument #11357 - Fix the issue that an error is reported by the
PARTITION BY LIST
statement. (Currently only the syntax is supported; when TiDB executes the statement, a regular table is created and a prompting message is provided) #11236 - Fix the issue that
Mod(%)
,Multiple(*)
, andMinus(-)
operations return an inconsistent0
result with that in MySQL when there are many decimal digits (such asselect 0.000 % 0.11234500000000000000
) #11353
- Fix the issue that the
- Server
- DDL
- Disallow dropping indexes on auto-increment columns to avoid incorrect results of the auto-increment columns caused by this operation #11402
- Fix the issue that the character set of the column is not correct when creating and modifying the table with different character sets and collations #11423
- Fix the issue that the column schema might get wrong when
alter table ... set default...
and another DDL statement that modifies this column are executed in parallel #11374 - Fix the issue that data fails to be backfilled when Generated Column A depends on Generated Column B and A is used to create an index #11538
- Speed up
ADMIN CHECK TABLE
operations #11538
TiKV
- Support returning an error message when the client accesses a TiKV Region that is being closed #4820
- Support reverse
raw_scan
andraw_batch_scan
interfaces #5148
Tools
- TiDB Binlog
- Add the
ignore-txn-commit-ts
configuration item in Drainer to skip executing some statements in a transaction #697 - Add the configuration item check on startup, which stops Pump and Drainer from running and returns an error message when meeting invalid configuration items #708
- Add the
node-id
configuration in Drainer to specify Drainer’s node ID #706
- Add the
- TiDB Lightning
- Fix the issue that
tikv_gc_life_time
fails to be changed back to its original value when 2 checksums are running at the same time #224
- Fix the issue that
TiDB Ansible
- Add the
log4j
configuration file in Spark #842 - Update the tispark jar package to v2.1.2 #863
- Fix the issue that the Prometheus configuration file is generated in the wrong format when TiDB Binlog uses Kafka or ZooKeeper #845
- Fix the bug that PD fails to switch the Leader when executing the
rolling_update.yml
operation #888 - Optimize the logic of rolling updating PD nodes - upgrade Followers first and then the Leader - to improve stability #895
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