From 0b2f83e079b500370784ae4838b247ab72cc2e82 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <d.koval@postgrespro.ru>
Date: Thu, 6 Jun 2024 19:53:15 +0300
Subject: [PATCH v1] LOCK TABLE with deadlocks

---
 .../test_misc/t/006_parallel_inserts.pl       | 77 +++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 src/test/modules/test_misc/t/006_parallel_inserts.pl

diff --git a/src/test/modules/test_misc/t/006_parallel_inserts.pl b/src/test/modules/test_misc/t/006_parallel_inserts.pl
new file mode 100644
index 0000000000..e8185ea188
--- /dev/null
+++ b/src/test/modules/test_misc/t/006_parallel_inserts.pl
@@ -0,0 +1,77 @@
+use strict;
+use warnings;
+
+use threads;
+use IPC::Run;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+my $THREADS = 4;
+my $ROWS = 365;
+
+# Initialize new node.
+my $node = PostgreSQL::Test::Cluster->new("node");
+$node->init();
+$node->start;
+
+# Initial queries.
+$node->safe_psql("postgres", "
+CREATE TABLE test(i int, t text);
+CREATE TABLE test2(i int, t text);
+
+CREATE FUNCTION test_func() RETURNS trigger AS
+\$BODY\$
+DECLARE
+  q text;
+BEGIN
+  RAISE LOG 'Before lock (pid %)', pg_backend_pid();
+  LOCK TABLE test;
+  RAISE LOG 'After lock (pid %)', pg_backend_pid();
+  q = 'INSERT INTO test2 SELECT ((\$1)::test).*';
+  EXECUTE q USING NEW;
+  RETURN NULL;
+END;
+\$BODY\$ LANGUAGE plpgsql SECURITY DEFINER;
+
+CREATE TRIGGER test_trigger BEFORE INSERT ON test FOR EACH ROW EXECUTE PROCEDURE test_func();
+");
+
+# Invoke psql.
+sub psql_worker
+{
+	my ($worker_name) = @_;
+
+	for (my $j = 1; $j <= $ROWS; $j += 1)
+	{
+		my $query = qq[INSERT INTO test VALUES ($j, '$worker_name');];
+		my @cmd = ['psql', '-XAtq', '-d', $node->connstr('postgres'), '-v', 'ON_ERROR_STOP=1', '-c', $query];
+
+		print("# Executing: $query\n");
+		IPC::Run::run @cmd;
+	}
+}
+
+# Start the workers.
+my @workers;
+for (my $i = 1; $i <= $THREADS; $i += 1)
+{
+	my $worker_name_i = "worker_$i";
+	print("# Worker: $worker_name_i\n");
+	push @workers, threads->create('psql_worker', $worker_name_i);
+}
+
+# Wait for the workers to finish.
+foreach my $thr (@workers)
+{
+	$thr->join();
+}
+
+# Check rows.
+my $psql_stdout;
+$node->psql('postgres', q(SELECT count(*) FROM test2;), stdout => \$psql_stdout);
+is($psql_stdout, $ROWS * $THREADS, 'rows amount');
+
+# Done.
+$node->stop;
+done_testing();
-- 
2.34.1