mysql> select * from information_schema.innodb_trx\G
*************************** 1. row ***************************
                    trx_id: 3795
                 trx_state: LOCK WAIT
               trx_started: 2022-10-11 16:03:38
     trx_requested_lock_id: 139727275779216:52:4:3:139724882995456
          trx_wait_started: 2022-10-11 16:03:38
                trx_weight: 2
       trx_mysql_thread_id: 9346
                 trx_query: update t set b=0 where a=8
       trx_operation_state: starting index read
         trx_tables_in_use: 1
         trx_tables_locked: 1
          trx_lock_structs: 2
     trx_lock_memory_bytes: 1128
           trx_rows_locked: 1
         trx_rows_modified: 0
   trx_concurrency_tickets: 0
       trx_isolation_level: READ COMMITTED
         trx_unique_checks: 1
    trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
 trx_adaptive_hash_latched: 0
 trx_adaptive_hash_timeout: 0
          trx_is_read_only: 0
trx_autocommit_non_locking: 0
       trx_schedule_weight: 1
*************************** 2. row ***************************
                    trx_id: 3790
                 trx_state: RUNNING
               trx_started: 2022-10-11 16:03:29
     trx_requested_lock_id: NULL
          trx_wait_started: NULL
                trx_weight: 3
       trx_mysql_thread_id: 9320
                 trx_query: NULL
       trx_operation_state: NULL
         trx_tables_in_use: 0
         trx_tables_locked: 1
          trx_lock_structs: 2
     trx_lock_memory_bytes: 1128
           trx_rows_locked: 1
         trx_rows_modified: 1
   trx_concurrency_tickets: 0
       trx_isolation_level: READ COMMITTED
         trx_unique_checks: 1
    trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
 trx_adaptive_hash_latched: 0
 trx_adaptive_hash_timeout: 0
          trx_is_read_only: 0
trx_autocommit_non_locking: 0
       trx_schedule_weight: NULL
2 rows in set (0.00 sec)
说明：通过InnoDB的事务表innodb_trx查询到thread_id=9346的事务3795正在等待锁（trx_state: LOCK WAIT）,
thread_id=9320的事务3790正在执行（trx_state: RUNNING）。
mysql> select * from performance_schema.data_locks\G
*************************** 1. row ***************************
               ENGINE: INNODB
       ENGINE_LOCK_ID: 139727275779216:1113:139724882998560
ENGINE_TRANSACTION_ID: 3795
            THREAD_ID: 9441
             EVENT_ID: 5000
        OBJECT_SCHEMA: testdb
          OBJECT_NAME: t
       PARTITION_NAME: NULL
    SUBPARTITION_NAME: NULL
           INDEX_NAME: NULL
OBJECT_INSTANCE_BEGIN: 139724882998560
            LOCK_TYPE: TABLE
            LOCK_MODE: IX
          LOCK_STATUS: GRANTED
            LOCK_DATA: NULL
*************************** 2. row ***************************
               ENGINE: INNODB
       ENGINE_LOCK_ID: 139727275779216:52:4:3:139724882995456
ENGINE_TRANSACTION_ID: 3795
            THREAD_ID: 9441
             EVENT_ID: 5012
        OBJECT_SCHEMA: testdb
          OBJECT_NAME: t
       PARTITION_NAME: NULL
    SUBPARTITION_NAME: NULL
           INDEX_NAME: PRIMARY
OBJECT_INSTANCE_BEGIN: 139724882995456
            LOCK_TYPE: RECORD
            LOCK_MODE: X,REC_NOT_GAP
          LOCK_STATUS: WAITING
            LOCK_DATA: 8
*************************** 3. row ***************************
               ENGINE: INNODB
       ENGINE_LOCK_ID: 139727275781640:1113:139724883017072
ENGINE_TRANSACTION_ID: 3790
            THREAD_ID: 9415
             EVENT_ID: 15467
        OBJECT_SCHEMA: testdb
          OBJECT_NAME: t
       PARTITION_NAME: NULL
    SUBPARTITION_NAME: NULL
           INDEX_NAME: NULL
OBJECT_INSTANCE_BEGIN: 139724883017072
            LOCK_TYPE: TABLE
            LOCK_MODE: IX
          LOCK_STATUS: GRANTED
            LOCK_DATA: NULL
*************************** 4. row ***************************
               ENGINE: INNODB
       ENGINE_LOCK_ID: 139727275781640:52:4:3:139724883013968
ENGINE_TRANSACTION_ID: 3790
            THREAD_ID: 9441
             EVENT_ID: 5007
        OBJECT_SCHEMA: testdb
          OBJECT_NAME: t
       PARTITION_NAME: NULL
    SUBPARTITION_NAME: NULL
           INDEX_NAME: PRIMARY
OBJECT_INSTANCE_BEGIN: 139724883013968
            LOCK_TYPE: RECORD
            LOCK_MODE: X,REC_NOT_GAP
          LOCK_STATUS: GRANTED
            LOCK_DATA: 8
4 rows in set (0.00 sec)
说明：事务3795正在等待LOCK_TYPE: RECORD，LOCK_MODE:X,REC_NOT_GAP，等待的主键值为8；
事务3790已获取主键值为8的LOCK_TYPE: RECORD，LOCK_MODE:X,REC_NOT_GAP锁。
mysql> select * from sys.innodb_lock_waits\G
*************************** 1. row ***************************
                wait_started: 2022-10-11 16:03:38
                    wait_age: 00:02:50
               wait_age_secs: 170
                locked_table: `testdb`.`t`
         locked_table_schema: testdb
           locked_table_name: t
      locked_table_partition: NULL
   locked_table_subpartition: NULL
                locked_index: PRIMARY
                 locked_type: RECORD
              waiting_trx_id: 3795
         waiting_trx_started: 2022-10-11 16:03:38
             waiting_trx_age: 00:02:50
     waiting_trx_rows_locked: 1
   waiting_trx_rows_modified: 0
                 waiting_pid: 9346
               waiting_query: update t set b=0 where a=8
             waiting_lock_id: 139727275779216:52:4:3:139724882995456
           waiting_lock_mode: X,REC_NOT_GAP
             blocking_trx_id: 3790
                blocking_pid: 9320
              blocking_query: NULL
            blocking_lock_id: 139727275781640:52:4:3:139724883013968
          blocking_lock_mode: X,REC_NOT_GAP
        blocking_trx_started: 2022-10-11 16:03:29
            blocking_trx_age: 00:02:59
    blocking_trx_rows_locked: 1
  blocking_trx_rows_modified: 1
     sql_kill_blocking_query: KILL QUERY 9320
sql_kill_blocking_connection: KILL 9320
1 row in set (0.01 sec)
说明：事务3795等待testdb.t上的rec_not_gap独占锁，事务3790持有该独占锁。
mysql> select distinct,* from sys.processlist where conn_id in (select trx_mysql_thread_id from information_schema.innodb_trx)\G
*************************** 1. row ***************************
                thd_id: 9441
               conn_id: 9346
                  user: admin@172.17.128.73
                    db: testdb
               command: Query
                 state: updating
time: 141
     current_statement: update t set b=0 where a=8
     statement_latency: 2.37 min
              progress: NULL
          lock_latency: 431.00 us
         rows_examined: 0
             rows_sent: 0
         rows_affected: 0
            tmp_tables: 0
       tmp_disk_tables: 0
             full_scan: NO
        last_statement: NULL
last_statement_latency: NULL
        current_memory: 140.15 KiB
             last_wait: wait/io/table/sql/handler
     last_wait_latency: Still Waiting
                source: handler.cc:3250
           trx_latency: 13.30 min
             trx_state: ACTIVE
        trx_autocommit: NO
                   pid: 9632
          program_name: mysql
*************************** 2. row ***************************
                thd_id: 9415
               conn_id: 9320
                  user: admin@172.17.128.73
                    db: testdb
               command: Sleep
                 state: NULL
time: 801
     current_statement: NULL
     statement_latency: NULL
              progress: NULL
          lock_latency: 288.00 us
         rows_examined: 0
             rows_sent: 0
         rows_affected: 1
            tmp_tables: 0
       tmp_disk_tables: 0
             full_scan: NO
        last_statement: insert into t values(8,8)
last_statement_latency: 765.23 us
        current_memory: 218.19 KiB
             last_wait: wait/io/socket/sql/client_connection
     last_wait_latency: Still Waiting
                source: viosocket.cc:146
           trx_latency: 13.52 min
             trx_state: ACTIVE
        trx_autocommit: NO
                   pid: 9600
          program_name: mysql
说明：被阻塞事务执行的sql语句update t set b=0 where a=8，
阻塞事务执行的sql语句是insert into t values(8,8)。