--  citus--8.0-6--8.0-7
SET search_path = 'pg_catalog';

CREATE VIEW citus.citus_lock_waits AS

WITH
citus_dist_stat_activity AS
(
  SELECT * FROM citus_dist_stat_activity
),
unique_global_wait_edges AS
(
	SELECT DISTINCT ON(waiting_node_id, waiting_transaction_num, blocking_node_id, blocking_transaction_num) * FROM dump_global_wait_edges()
),
citus_dist_stat_activity_with_node_id AS
(
  SELECT
  citus_dist_stat_activity.*, (CASE citus_dist_stat_activity.master_query_host_name WHEN 'coordinator_host' THEN 0 ELSE pg_dist_node.nodeid END) as initiator_node_id
  FROM
  citus_dist_stat_activity LEFT JOIN pg_dist_node
  ON
  citus_dist_stat_activity.master_query_host_name = pg_dist_node.nodename AND
  citus_dist_stat_activity.master_query_host_port = pg_dist_node.nodeport
)
SELECT
 waiting.pid AS waiting_pid,
 blocking.pid AS blocking_pid,
 waiting.query AS blocked_statement,
 blocking.query AS current_statement_in_blocking_process,
 waiting.initiator_node_id AS waiting_node_id,
 blocking.initiator_node_id AS blocking_node_id,
 waiting.master_query_host_name AS waiting_node_name,
 blocking.master_query_host_name AS blocking_node_name,
 waiting.master_query_host_port AS waiting_node_port,
 blocking.master_query_host_port AS blocking_node_port
FROM
 unique_global_wait_edges
JOIN
 citus_dist_stat_activity_with_node_id waiting ON (unique_global_wait_edges.waiting_transaction_num = waiting.transaction_number AND unique_global_wait_edges.waiting_node_id = waiting.initiator_node_id)
JOIN
 citus_dist_stat_activity_with_node_id blocking ON (unique_global_wait_edges.blocking_transaction_num = blocking.transaction_number AND unique_global_wait_edges.blocking_node_id = blocking.initiator_node_id);

ALTER VIEW citus.citus_lock_waits SET SCHEMA pg_catalog;
GRANT SELECT ON pg_catalog.citus_lock_waits TO PUBLIC;

RESET search_path;

