Coprocessor (PROCESSED_KEYS �→ ) and request units (RU) as identifying �→ conditions, and puts identified queries into the specified resource �→ group for more precise identification queries, avoiding identification bias when overall performance decreases. You can set multiple conditions simultaneously, and a query is identified as a runaway query if any condition is met. You can performance when querying tables with numerous columns #52112 @Rustin170506 85 • Simplify filter conditions like a = 1 AND (a > 1 OR (a = 1 AND b = 2)) to a �→ = 1 AND b = 2 #56005 @ghazalfamilyusa • Increase

Coprocessor (PROCESSED_KEYS �→ ) and request units (RU) as identifying �→ conditions, and puts identified queries into the specified resource �→ group for more precise identification queries, avoiding identification bias when overall performance decreases. You can set multiple conditions simultaneously, and a query is identified as a runaway query if any condition is met. You can performance when querying tables with numerous columns #52112 @Rustin170506 80 • Simplify filter conditions like a = 1 AND (a > 1 OR (a = 1 AND b = 2)) to a �→ = 1 AND b = 2 #56005 @ghazalfamilyusa • Increase

generates an execution plan, it only needs statistics for some columns, such as columns in the filter conditions, columns in the join keys, and columns used for aggregation. Starting from v8.3.0, TiDB continuously USING ( ... ) statement #54162 @dveeden • Construct more precise index access ranges for filter conditions like ((idx_col_1 �→ > 1)or (idx_col_1 = 1 and idx_col_2 > 10))and ((idx_col_1 < 10) �→ or (idx_col_1 outside the set time window #55283 @hawkingrei • Adjust estimation results from 0 to 1 for equality conditions that do not hit TopN when statistics are entirely composed of TopN and the modified row count in

when creating a table with foreign keys #53652 @hawkingrei • Fix the issue that certain filter conditions in queries might cause the planner module to report an invalid memory address or nil pointer dereference +------+ 1 rows in set (0.00 sec) 109 Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 3.3.7 Create, authorize, and delete | +------+ 1 rows in set (0.00 sec) Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person WHERE id < 5; 4.2.2.6 Need help? Ask the community

@ywqzzy • Enhance the handling of DNF items that are always false by directly ignoring such filter conditions, thus avoiding unnecessary full table scans #40997 @hi- rustin • Support using Optimizer Fix Controls +------+ 1 rows in set (0.00 sec) 109 Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 3.3.7 Create, authorize, and delete | +------+ 1 rows in set (0.00 sec) Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person WHERE id < 5; 4.2.2.6 Need help? Ask the community

In v8.0.0, the concurrent HashAgg algorithm of TiDB supports disk spill. Under any concurrent conditions, the HashAgg operator can automatically trigger data spill based on memory usage, thus balancing statistics collection dynamically sets priorities for ob- jects in combination with a variety of conditions to ensure that more deserving candi- dates are processed in priority, such as newly created indexes optimizer can identify the one with lower cost. • When using OR to connect multiple member of conditions, the optimizer can match an effective index partial path for each DNF item (a member of condition)

@ywqzzy • Enhance the handling of DNF items that are always false by directly ignoring such filter conditions, thus avoiding unnecessary full table scans #40997 @hi- rustin • Support using Optimizer Fix Controls +------+ 1 rows in set (0.00 sec) 105 Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 3.3.7 Create, authorize, and delete | +------+ 1 rows in set (0.00 sec) Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person WHERE id < 5; 4.3 Example Applications 4.3

the execution performance of SEMI JOIN and LEFT OUTER SEMIJOIN �→ when only JOIN KEY equality conditions are included in JOIN ON #47424 @gengliqi • Tools • Backup & Restore (BR) • Introduce a new | +------+ 1 rows in set (0.00 sec) Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 3.3.7 Create, authorize, and delete +------+ 1 rows in set (0.00 sec) 131 Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person WHERE id < 5; 4.3 Example Applications 4.3

conflicts and lock waits of pessimistic locks, which helps DBAs to observe transaction locking conditions and troubleshoot deadlock problems. #24199 User document: – View the pessimistic locks and other +------+ | name | +------+ | tom | +------+ Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 86 3.2.7 Create, authorize, and time. You can check whether the problem is in the statistics by executing select count(*) for the conditions on TableScan/ �→ IndexScan and comparing the row count information in the explain result. • 3

+------+ 1 rows in set (0.00 sec) 106 Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person where id<5; 3.3.7 Create, authorize, and delete | +------+ 1 rows in set (0.00 sec) Use the WHERE clause to filter all records that match the conditions and then return the result: SELECT * FROM person WHERE id < 5; 4.3 Example Applications 4.3 DELETE FROM {table} WHERE {filter} Parameter Name Description {table} Table name {filter} Matching conditions of the filter This example only shows a simple use case of DELETE. For detailed information, see