Identifying blocking queries on MySQL 5.5
This query may assist in your search for locking and blocking ids.

# IS-tx-wait-block-qrys.sql to help research BUSY systems Last Updated 20191227 wh
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# From article at 
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# 20191227 tested on MariaDB 10.3.10


SELECT r.trx_id waiting_trx_id, r.trx_mysql_thread_id waiting_thread, r.trx_query waiting_query, b.trx_id blocking_trx_id, b.trx_mysql_thread_id blocking_thread, b.trx_query blocking_query FROM information_schema.innodb_lock_waits w INNER JOIN information_schema.innodb_trx b ON b.trx_id = w.blocking_trx_id INNER JOIN information_schema.innodb_trx r ON r.trx_id = w.requesting_trx_id;