Clean up duplicate node entries on vlan 0

Netdisco/lib/App/Netdisco/DB.pm

@@ -11,7 +11,7 @@ __PACKAGE__->load_namespaces(
 );
 
 our # try to hide from kwalitee
-  $VERSION = 38; # schema version used for upgrades, keep as integer
+  $VERSION = 39; # schema version used for upgrades, keep as integer
 
 use Path::Class;
 use File::Basename;

Netdisco/lib/App/Netdisco/DB/schema_versions/App-Netdisco-DB-38-39-PostgreSQL.sql

@@ -0,0 +1,17 @@
+-- clean up node table where vlan = 0 and vlan = <another number>
+-- 
+-- DELETE n1.*
+--   FROM node n1 INNER JOIN
+--     (SELECT mac, switch, port from node
+--       GROUP BY mac, switch, port
+--       HAVING count(*) > 1) n2
+--     ON n1.mac = n2.mac
+--       AND n1.switch = n2.switch
+--       AND n1.port = n2.port
+--       AND n1.vlan = '0';
+
+BEGIN;
+
+DELETE n1.* FROM node n1 INNER JOIN (SELECT mac, switch, port from node GROUP BY mac, switch, port HAVING count(*) > 1) n2 ON n1.mac = n2.mac AND n1.switch = n2.switch AND n1.port = n2.port AND n1.vlan = '0';
+
+COMMIT;

Netdisco/lib/App/Netdisco/Manual/ReleaseNotes.pod

@@ -38,6 +38,14 @@ but they are backwards compatible.
 
 =head1 2.029000
 
+=head2 Health Advice
+
+This release will remove from the database spurious Node (workstation,
+printer, etc) entries on vlan 0, which were causing dupliate entries in the
+web interface. We advise that you back up the database prior to upgrade:
+
+ /usr/bin/pg_dump -F p --create -f netdisco-pgsql.dump netdisco
+
 =head2 General Notices
 
 The configuration item C<reports> is now a list (used to be a dictionary).