tidb_audit_enabled = 0; admin plugins enable audit; admin plugins disable audit; The number of audit event classes for one SQL statement One or more One Modify the auditing objects Create the filter by using Event Classes based on the type of SQL statements. A SQL statement corresponds to one or more event classes. One event class can be a subclass of another event class. For example: ● The event classes for ● The event classes for INSERT INTO t VALUES (1),(2),(3) are QUERY, QUERY_DML and INSERT. QUERY_DML is a subclass of QUERY, and INSERT is a subclass of QUERY_DML. ● The event classes for SET GLOBAL

published Large-scale Incremental Processing Using Distributed Transactions and Notifications, which de- scribed Percolator: a Google-internal database for ran- dom access transactional workloads where low tested TiDB 2.1.7, 2.1.8, 3.0.0-beta.1, 3.0.0-beta.1- 40, and 3.0.0-rc.2. Our tests ran on a five-node De- bian Stretch cluster, with PD, TiKV, and TiDB on each node. We used a replication factor of 3 for TiDB, we developed a new, more general approach for verifying transactional isolation, based on cycle de- tection.1 The monotonic test finds dependency cycles over increment-only registers, the txn-cycle

System variables Variable name Change type Description tidb_enable_list_partition �→ ModifiedThe de- fault value is changed from OFF to ON. 41 Variable name Change type Description tidb_mem_quota_query rithm of TiDB sup- ports Outer Join. This vari- able con- trols the sup- port be- hav- ior, and the de- fault value is ON. 48 Variable name Change type Description tidb_enable_prepared_plan_cache �→ Modified The de- fault value is changed from FALSE �→ to TRUE �→ . 68 Configuration file Configuration Change type Description TiKVregion �→ - �→ max �→ - �→ keys �→ Modified The de- fault value is

tests, mean- ing that the sup- port of Outer Join for the Join Re- order algo- rithm is en- abled by de- fault. 45 Variable name Change type Description tidb_cost_model_version �→ Modified Changes the tests, mean- ing that Cost Model Version 2 is used for index selec- tion and op- erator selec- tion by de- fault. 46 Variable name Change type Description tidb_enable_gc_aware_memory_track �→ Modified value from OFF to ON after further tests, mean- ing that the meta- data lock feature is en- abled by de- fault. 48 Variable name Change type Description tidb_enable_tiflash_read_for_write_stmt �→ Modified

value from 500ms to 100ms after op- timizing the algo- rithm to improve the sensi- tivity of slow node de- tection. 46 Configuration file Configuration parame- ter Change type Description TiKV raftstore 5.1 5.0 CMSketch Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Y Y Y Histograms Y Y ta- bles - sum- mary per- sis- tence E E N N N N N N N N Slow query log Y Y Y Y Y Y Y Y Y Y TiUP de- ploy- ment Y Y Y Y Y Y Y Y Y Y Kubernetes op- era- tor Y Y Y Y Y Y Y Y Y Y Built- in phys- ical

that TiDB uses the value of the config- uration item txn- �→ entry �→ - �→ size �→ - �→ limit �→ by de- fault. When this vari- able is set to a non- zero value, txn- �→ entry �→ - �→ size �→ - �→ limit CMSketch Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Y Y Y Histograms bles - sum- mary per- sis- tence E E E N N N N N N N N Slow query log Y Y Y Y Y Y Y Y Y Y Y TiUP de- ploy- ment Y Y Y Y Y Y Y Y Y Y Y Kubernetes op- er- a- tor Y Y Y Y Y Y Y Y Y Y Y Built- in phys-

transmission #7084 @solotzg The TiFlash MPP mode supports multiple Join algorithms. Before v7.1.0, TiDB de- termines whether the MPP mode uses the Broadcast Hash Join algorithm based on the tidb_broadcast_ value from OFF to ON, mean- ing that the Ti- Flash late materi- aliza- tion feature is en- abled by de- fault. authentication_ldap_sasl_auth_method_name �→ Newly added Specifies the au- thenti- cation 5.4 5.3 5.2 5.1 5.0 CMSketch Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Y Y Y Histograms Y Y Y Y Y Y Y Y

depre- cated. Its value will be fixed to the default value ON, that is, global index is en- abled by de- fault. You only need to add the key- word GLOBAL to the corre- spond- ing column when execut- ing cated. Its value will be fixed to the default value ON, that is, list parti- tioning is en- abled by de- fault. 50 Variable name Change type Description tidb_ �→ enable �→ _ �→ table �→ _ �→ partition cated. Its value will be fixed to the default value ON, that is, table parti- tioning is en- abled by de- fault. tidb_ �→ analyze �→ _ �→ partition �→ _ �→ concurrency �→ Modified Changes the value range

default value from OFF to ON. This means that Dis- tributed eXecu- tion Frame- work (DXF) is en- abled by de- fault, which fully utilizes the re- sources of the TiDB cluster and greatly im- proves the perfor- the conflict.strategy parameter. The duplicate-resolution parameter for the old version of conflict de- tection will be removed in a future release. 51 2.2.4 Improvements • TiDB • Improve the MySQL 3 5.2 5.1 CMSketchDisabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Disabled by de- fault Y Y HistogramsY Y Y Y

depre- cated. Its value will be fixed to the default value ON, that is, global index is en- abled by de- fault. You only need to add the key- word GLOBAL to the corre- spond- ing column when execut- ing cated. Its value will be fixed to the default value ON, that is, list parti- tioning is en- abled by de- fault. 55 Variable name Change type Description tidb_ �→ enable �→ _ �→ table �→ _ �→ partition cated. Its value will be fixed to the default value ON, that is, table parti- tioning is en- abled by de- fault. tidb_ �→ analyze �→ _ �→ partition �→ _ �→ concurrency �→ Modified Changes the value range