diff --git a/test/t/007_inserts.pl b/test/t/007_inserts.pl
index 40681de..01b2644 100644
--- a/test/t/007_inserts.pl
+++ b/test/t/007_inserts.pl
@@ -4,6 +4,10 @@ use PostgresNode;
 use TestLib;
 use Test::More tests => 3;
 
+# TODO fix randomness
+
+my $dim = 768;
+
 # Initialize node
 my $node = get_new_node('node');
 $node->init;
@@ -11,9 +15,9 @@ $node->start;
 
 # Create table and index
 $node->safe_psql("postgres", "CREATE EXTENSION vector;");
-$node->safe_psql("postgres", "CREATE TABLE tst (v vector(768));");
+$node->safe_psql("postgres", "CREATE TABLE tst (v vector($dim));");
 $node->safe_psql("postgres",
-	"INSERT INTO tst SELECT (SELECT array_agg(random()) FROM generate_series(1, 768)) FROM generate_series(1, 10000) i;"
+	"INSERT INTO tst SELECT (SELECT array_agg(random()) FROM generate_series(1, $dim)) FROM generate_series(1, 10000) i;"
 );
 $node->safe_psql("postgres", "CREATE INDEX ON tst USING ivfflat (v);");
 
@@ -24,10 +28,6 @@ $node->pgbench(
 	[qr{^$}],
 	"concurrent INSERTs",
 	{
-		"007_concurrent" => q(
-			BEGIN;
-			INSERT INTO tst SELECT (SELECT array_agg(random()) FROM generate_series(1, 768)) FROM generate_series(1, 10) i;
-			COMMIT;
-		),
+		"007_concurrent" => "INSERT INTO tst SELECT (SELECT array_agg(random()) FROM generate_series(1, $dim)) FROM generate_series(1, 10) i;"
 	}
 );