- Introduction
- Concepts
- Architecture
- Key Features
- Horizontal Scalability
- MySQL Compatible Syntax
- Replicate from and to MySQL
- Distributed Transactions with Strong Consistency
- Cloud Native Architecture
- Minimize ETL with HTAP
- Fault Tolerance & Recovery with Raft
- Automatic Rebalancing
- Deployment and Orchestration with Ansible, Kubernetes, Docker
- JSON Support
- Spark Integration
- Read Historical Data Without Restoring from Backup
- Fast Import and Restore of Data
- Hybrid of Column and Row Storage
- SQL Plan Management
- Open Source
- Online Schema Changes
- How-to
- Get Started
- Deploy
- Hardware Recommendations
- From Binary Tarball
- Orchestrated Deployment
- Geographic Redundancy
- Data Migration with Ansible
- Configure
- Secure
- Transport Layer Security (TLS)
- Generate Self-signed Certificates
- Monitor
- Migrate
- Maintain
- Scale
- Upgrade
- Troubleshoot
- Reference
- SQL
- MySQL Compatibility
- SQL Language Structure
- Data Types
- Functions and Operators
- Function and Operator Reference
- Type Conversion in Expression Evaluation
- Operators
- Control Flow Functions
- String Functions
- Numeric Functions and Operators
- Date and Time Functions
- Bit Functions and Operators
- Cast Functions and Operators
- Encryption and Compression Functions
- Information Functions
- JSON Functions
- Aggregate (GROUP BY) Functions
- Miscellaneous Functions
- Precision Math
- SQL Statements
ADD COLUMN
ADD INDEX
ADMIN
ADMIN CANCEL DDL
ADMIN CHECKSUM TABLE
ADMIN CHECK [TABLE|INDEX]
ADMIN SHOW DDL [JOBS|QUERIES]
ALTER DATABASE
ALTER TABLE
ALTER USER
ANALYZE TABLE
BEGIN
CHANGE COLUMN
COMMIT
CREATE DATABASE
CREATE INDEX
CREATE TABLE LIKE
CREATE TABLE
CREATE USER
DEALLOCATE
DELETE
DESC
DESCRIBE
DO
DROP COLUMN
DROP DATABASE
DROP INDEX
DROP TABLE
DROP USER
EXECUTE
EXPLAIN ANALYZE
EXPLAIN
FLUSH PRIVILEGES
FLUSH STATUS
FLUSH TABLES
GRANT <privileges>
INSERT
KILL [TIDB]
LOAD DATA
LOAD STATS
MODIFY COLUMN
PREPARE
RENAME INDEX
RENAME TABLE
REPLACE
REVOKE <privileges>
ROLLBACK
SELECT
SET [NAMES|CHARACTER SET]
SET PASSWORD
SET TRANSACTION
SET [GLOBAL|SESSION] <variable>
SHOW CHARACTER SET
SHOW COLLATION
SHOW [FULL] COLUMNS FROM
SHOW CREATE TABLE
SHOW DATABASES
SHOW ENGINES
SHOW ERRORS
SHOW [FULL] FIELDS FROM
SHOW GRANTS
SHOW INDEXES [FROM|IN]
SHOW INDEX [FROM|IN]
SHOW KEYS [FROM|IN]
SHOW PRIVILEGES
SHOW [FULL] PROCESSSLIST
SHOW SCHEMAS
SHOW STATUS
SHOW [FULL] TABLES
SHOW TABLE STATUS
SHOW [GLOBAL|SESSION] VARIABLES
SHOW WARNINGS
START TRANSACTION
TRACE
TRUNCATE
UPDATE
USE
- Constraints
- Generated Columns
- Character Set
- Configuration
- Security
- Transactions
- System Databases
- Errors Codes
- Supported Client Drivers
- Garbage Collection (GC)
- Performance
- Key Monitoring Metrics
- Alert Rules
- Best Practices
- TiSpark
- TiDB Binlog
- Tools
- Overview
- Use Cases
- Download
- Mydumper
- Syncer
- Loader
- TiDB Data Migration
- TiDB Lightning
- sync-diff-inspector
- PD Control
- PD Recover
- TiKV Control
- TiDB Control
- FAQs
- Support
- Contribute
- Releases
- All Releases
- v2.1
- v2.0
- v1.0
- Glossary
Important
You are viewing the documentation of an older version of the TiDB database (TiDB v2.1).
It is recommended that you use the latest LTS version of the TiDB database.
TiDB 2.1.8 Release Notes
Release date: April 12, 2019
TiDB version: 2.1.8
TiDB Ansible version: 2.1.8
TiDB
- Fix the issue that the processing logic of
GROUP_CONCAT
function is incompatible with MySQL when there is a NULL-valued parameter #9930 - Fix the equality check issue of decimal values in the
Distinct
mode #9931 - Fix the collation compatibility issue of the date, datetime, and timestamp types for the
SHOW FULL COLUMNS
statement - Fix the issue that the row count estimation is inaccurate when the filtering condition contains correlated columns #9937
- Fix the compatibility issue between the
DATE_ADD
andDATE_SUB
functions - Support the
%H
format for theSTR_TO_DATE
function to improve compatibility #9964 - Fix the issue that the result is wrong when the
GROUP_CONCAT
function groups by a unique index #9969 - Return a warning when the Optimizer Hints contains an unmatched table name #9970
- Unify the log format to facilitate collecting logs using tools for analysis Unified Log Format
- Fix the issue that a lot of NULL values cause inaccurate statistics estimation #9979
- Fix the issue that an error is reported when the default value of the TIMESTAMP type is the boundary value #9987
- Validate the value of
time_zone
#10000 - Support the
2019.01.01
time format #10001 - Fix the issue that the row count estimation is displayed incorrectly in the result returned by the
EXPLAIN
statement in some cases #10044 - Fix the issue that
KILL TIDB [session id]
cannot instantly stop the execution of a statement in some cases #9976 - Fix the predicate pushdown issue of constant filtering conditions in some cases #10049
- Fix the issue that a read-only statement is not processed correctly in some cases #10048
PD
- Fix the issue that
regionScatterer
might generate an invalidOperatorStep
#1482 - Fix the issue that a hot store makes incorrect statistics of keys #1487
- Fix the too short timeout issue of the
MergeRegion
operator #1495 - Add elapsed time metrics of the PD server handling TSO requests #1502
TiKV
- Fix the issue of wrong statistics of the read traffic #4441
- Fix the raftstore performance issue when too many Regions exist #4484
- Do not ingest files when the number of level 0 SST files exceeds
level_zero_slowdown_writes_trigger/2
#4464
Tools
- Optimize the order of importing tables for Lightning to reduce the effects of large tables executing
Checksum
andAnalyze
on the cluster during the importing process and improve the success rate ofChecksum
andAnalyze
#156 - Improve the encoding SQL performance by 50% for Lightning by directly parsing the data source file content to
types.Datum
of TiDB to avoid additional parsing working of the KV encoder #145 - Add the
storage.sync-log
configuration item in TiDB Binlog Pump to support flushing disks of the local storage asynchronously in Pump #529 - Support traffic compression of communication between TiDB Binlog Pump and Drainer #530
- Add the
syncer.sql-mode
configuration item in TiDB Binlog Drainer to support using differentsql-mode
s to parse DDL queries #513 - Add the
syncer.ignore-table
configuration item in TiDB Binlog Drainer to support filtering tables not to be replicated #526
TiDB Ansible
- Modify the version limit for the operating system and only support CentOS 7.0 or later and Red Hat 7.0 or later #734
- Add the feature of checking whether
epollexclusive
is supported in every OS #728 - Add the version limit for rolling update to prohibit upgrading a version of 2.0.1 or earlier to a version of 2.1 or later #728
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