tdsql [(none)]> SELECT * FROM performance_schema.data_locks \\G
*************************** 1. row ***************************
                             ENGINE: RocksDB
                     ENGINE_LOCK_ID: 28681376014270466_(0000279780000006,00002798)
              ENGINE_TRANSACTION_ID: 28681376014270466
                          THREAD_ID: 44
                           EVENT_ID: NULL
                      OBJECT_SCHEMA: testdb
                        OBJECT_NAME: test
                     PARTITION_NAME: NULL
                  SUBPARTITION_NAME: NULL
                         INDEX_NAME: NULL
              OBJECT_INSTANCE_BEGIN: 140502282795216
                          LOCK_TYPE: PRE_RANGE
                          LOCK_MODE: Write
                        LOCK_STATUS: GRANTED
                          LOCK_DATA: NULL
                          START_KEY: 0000279780000006
                            END_KEY: 00002798
                  EXCLUDE_START_KEY: 1
           BLOCKING_TRANSACTION_NUM: 0
BLOCKING_CHECK_READ_TRANSACTION_NUM: 0
                    READ_LOCKED_NUM: 0
                          TINDEX_ID: 10135
                    DATA_SPACE_TYPE: DATA_SPACE_TYPE_USER
               REPLICATION_GROUP_ID: 257
                KEY_RANGE_REGION_ID: 7312
                     PROCESSLIST_ID: 2097282
                            NODE_ID: 2
                          NODE_NAME: node-1-002
*************************** 2. row ***************************
                             ENGINE: RocksDB
                     ENGINE_LOCK_ID: 28681376014270466_0000279780000006
              ENGINE_TRANSACTION_ID: 28681376014270466
                          THREAD_ID: 44
                           EVENT_ID: NULL
                      OBJECT_SCHEMA: testdb
                        OBJECT_NAME: test
                     PARTITION_NAME: NULL
                  SUBPARTITION_NAME: NULL
                         INDEX_NAME: NULL
              OBJECT_INSTANCE_BEGIN: 140507882943448
                          LOCK_TYPE: KEY
                          LOCK_MODE: Write
                        LOCK_STATUS: GRANTED
                          LOCK_DATA: NULL
                          START_KEY: NULL
                            END_KEY: 0000279780000006
                  EXCLUDE_START_KEY: 0
           BLOCKING_TRANSACTION_NUM: 0
BLOCKING_CHECK_READ_TRANSACTION_NUM: 0
                    READ_LOCKED_NUM: 0
                          TINDEX_ID: 10135
                    DATA_SPACE_TYPE: DATA_SPACE_TYPE_USER
               REPLICATION_GROUP_ID: 257
                KEY_RANGE_REGION_ID: 7312
                     PROCESSLIST_ID: 1048704
                            NODE_ID: 1
                          NODE_NAME: node-1-001

-- Query the number of pessimistic locks on all nodes
SELECT COUNT(*) FROM performance_schema.data_locks \\G

-- Query all pessimistic lock information for key range region 7312 in replication group 257 across all nodes (querying by specifying only key_range_region_id is possible, though inefficient as it cannot leverage indexes to accelerate the query)
SELECT * FROM performance_schema.data_locks WHERE replication_group_id = 257 AND key_range_region_id = 7312 \\G

-- Query all pessimistic locks on all nodes that intersect with [0000279780000003, 0000279780000004].
SET @left = "0000279780000003";
SET @right = "0000279780000004";
SELECT * FROM performance_schema.data_locks WHERE
	(lock_type = 'KEY' AND @left <= end_key AND end_key <= @right) OR -- If it is a pessimistic lock on a single key, the corresponding key is stored in the end_key field; it is considered valid as long as end_key falls within the interval
    (lock_type = 'PRE_RANGE' AND @left < end_key AND (start_key < @right OR (NOT exclude_start_key and start_key = @right))) \\G -- If it is a pessimistic lock on a key interval, you need to judge whether [start_key, end_key) or (start_key, end_key) intersects with the interval based on exclude_start_key.

-- Query information about all pessimistic locks on the testdb.test table across all nodes.
-- First step: Obtain the tindex_id of testdb.test.
SELECT tindex_id FROM information_schema.statistics WHERE table_schema = 'testdb' AND table_name = 'test';
-- Second step: Use the tindex_id obtained in the first step to query lock information.
SELECT * FROM performance_schema.data_locks WHERE tindex_id = 12345;

-- Or directly use tableName databaseName to query the relevant pessimistic lock information
SELECT * FROM performance_schema.data_locks WHERE OBJECT_SCHEMA = 'testdb' AND OBJECT_NAME = 'test';

-- Query information about all pessimistic locks held by transaction 28681535313936395 on all nodes.
SELECT * FROM performance_schema.data_locks WHERE engine_transaction_id = 28681535313936395 \\G

-- Query information about all pessimistic locks on all nodes that are blocking transactions.
SELECT * FROM performance_schema.data_locks WHERE blocking_transaction_num > 0 OR blocking_check_read_transaction_num > 0 

BEGIN;
SELECT a FROM t FOR UPDATE;
SELECT SLEEP(100);

SELECT b FROM t FOR UPDATE;

SELECT c FROM t FOR UPDATE;