diff --git a/Netdisco/lib/App/Netdisco/DB/Result/Admin.pm b/Netdisco/lib/App/Netdisco/DB/Result/Admin.pm
index 71ad2f4e..fb98b3fa 100644
--- a/Netdisco/lib/App/Netdisco/DB/Result/Admin.pm
+++ b/Netdisco/lib/App/Netdisco/DB/Result/Admin.pm
@@ -54,9 +54,5 @@ __PACKAGE__->add_columns(
 
 __PACKAGE__->set_primary_key("job");
 
-__PACKAGE__->add_unique_constraint(
-  queued_job => [qw/ device action subaction /],
-);
-
 # You can replace this text with custom code or comments, and it will be preserved on regeneration
 1;
diff --git a/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-16-17-PostgreSQL.sql b/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-16-17-PostgreSQL.sql
index 75cca2c8..449db2d4 100644
--- a/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-16-17-PostgreSQL.sql
+++ b/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-16-17-PostgreSQL.sql
@@ -1,8 +1,12 @@
--- Convert schema '/home/devver/netdisco-ng/Netdisco/bin/../lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-16-PostgreSQL.sql' to '/home/devver/netdisco-ng/Netdisco/bin/../lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-17-PostgreSQL.sql':;
 
 BEGIN;
 
-ALTER TABLE admin ADD CONSTRAINT queued_job UNIQUE (device, action, subaction);
+CREATE UNIQUE INDEX jobs_queued ON admin (
+  action,
+  coalesce(subaction, '_x_'),
+  coalesce(device, '255.255.255.255'),
+  coalesce(port, '_x_')
+) WHERE status = 'queued';
 
 COMMIT;
 
diff --git a/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-17-PostgreSQL.sql b/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-17-PostgreSQL.sql
index 0aa4133d..e3a13042 100644
--- a/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-17-PostgreSQL.sql
+++ b/Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-17-PostgreSQL.sql
@@ -21,9 +21,15 @@ CREATE TABLE "admin" (
   "log" text,
   "debug" boolean,
   PRIMARY KEY ("job"),
-  CONSTRAINT "queued_job" UNIQUE ("device", "action", "subaction")
 );
 
+CREATE UNIQUE INDEX jobs_queued ON admin (
+  action,
+  coalesce(subaction, '_x_'),
+  coalesce(device, '255.255.255.255'),
+  coalesce(port, '_x_')
+) WHERE status = 'queued';
+
 --
 -- Table: device.
 --