diff --git a/titan/schema/dbapi-testdata.graphml b/titan/schema/dbapi-testdata.graphml
index fbf7e2b..952a62a 100644
--- a/titan/schema/dbapi-testdata.graphml
+++ b/titan/schema/dbapi-testdata.graphml
@@ -1 +1 @@
-<?xml version=\"1.0\" ?><graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\">    <key id=\"id\" for=\"node\" attr.name=\"id\" attr.type=\"string\"></key>    <key id=\"type\" for=\"node\" attr.name=\"type\" attr.type=\"string\"></key>    <key id=\"dpid\" for=\"node\" attr.name=\"dpid\" attr.type=\"string\"></key>    <key id=\"desc\" for=\"node\" attr.name=\"desc\" attr.type=\"string\"></key>    <key id=\"number\" for=\"node\" attr.name=\"number\" attr.type=\"int\"></key>    <key id=\"dl_addr\" for=\"node\" attr.name=\"dl_addr\" attr.type=\"string\"></key>    <key id=\"nw_addr\" for=\"node\" attr.name=\"nw_addr\" attr.type=\"string\"></key>    <key id=\"id\" for=\"edge\" attr.name=\"id\" attr.type=\"string\"></key>    <key id=\"source\" for=\"edge\" attr.name=\"source\" attr.type=\"string\"></key>    <key id=\"target\" for=\"edge\" attr.name=\"target\" attr.type=\"string\"></key>    <key id=\"label\" for=\"edge\" attr.name=\"label\" attr.type=\"string\"></key>    <graph id=\"G\" edgedefault=\"directed\">        <node id=\"1\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:01</data>            <data key=\"desc\">OpenFlow Switch at SEA</data>        </node>        <node id=\"2\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:02</data>            <data key=\"desc\">OpenFlow Switch at LAX</data>        </node>        <node id=\"3\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:03</data>            <data key=\"desc\">OpenFlow Switch at CHI</data>        </node>        <node id=\"4\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:04</data>            <data key=\"desc\">OpenFlow Switch at IAH</data>        </node>        <node id=\"5\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:05</data>            <data key=\"desc\">OpenFlow Switch at NYC</data>        </node>        <node id=\"6\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:06</data>            <data key=\"desc\">OpenFlow Switch at ATL</data>        </node>        <node id=\"100\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at SEA Switch</data>        </node>        <node id=\"101\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at SEA Switch</data>        </node>        <node id=\"102\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at SEA Switch</data>        </node>        <node id=\"103\">            <data key=\"type\">port</data>            <data key=\"number\">4</data>            <data key=\"desc\">port 4 at SEA Switch</data>        </node>        <node id=\"104\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at LAX Switch</data>        </node>        <node id=\"105\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at LAX Switch</data>        </node>        <node id=\"106\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at LAX Switch</data>        </node>        <node id=\"107\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at CHI Switch</data>        </node>        <node id=\"108\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at CHI Switch</data>        </node>        <node id=\"109\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at CHI Switch</data>        </node>        <node id=\"110\">            <data key=\"type\">port</data>            <data key=\"number\">4</data>            <data key=\"desc\">port 4 at CHI Switch</data>        </node>        <node id=\"111\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at IAH Switch</data>        </node>        <node id=\"112\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at IAH Switch</data>        </node>        <node id=\"113\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at IAH Switch</data>        </node>        <node id=\"114\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at NYC Switch</data>        </node>        <node id=\"115\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at NYC Switch</data>        </node>        <node id=\"116\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at NYC Switch</data>        </node>        <node id=\"117\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at ATL Switch</data>        </node>        <node id=\"118\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at ATL Switch</data>        </node>        <node id=\"119\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at ATL Switch</data>        </node>        <node id=\"1000\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">20:c9:d0:4a:e1:73</data>            <data key=\"nw_addr\">192.168.10.101</data>        </node>        <node id=\"1001\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">20:c9:d0:4a:e1:62</data>            <data key=\"nw_addr\">192.168.20.101</data>        </node>        <node id=\"1002\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">10:40:f3:e6:8d:55</data>            <data key=\"nw_addr\">192.168.10.1</data>        </node>        <node id=\"1003\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">a0:b3:cc:9c:c6:88</data>            <data key=\"nw_addr\">192.168.20.1</data>        </node>        <node id=\"1004\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">00:04:20:e2:50:a2</data>            <data key=\"nw_addr\">192.168.30.1</data>        </node>        <node id=\"1005\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">58:55:ca:c4:1b:a0</data>            <data key=\"nw_addr\">192.168.40.1</data>        </node>        <edge id=\"10000\" source=\"1\" target=\"101\" label=\"on\"></edge>        <edge id=\"10001\" source=\"1\" target=\"102\" label=\"on\"></edge>        <edge id=\"10002\" source=\"1\" target=\"103\" label=\"on\"></edge>        <edge id=\"10003\" source=\"2\" target=\"104\" label=\"on\"></edge>        <edge id=\"10004\" source=\"2\" target=\"105\" label=\"on\"></edge>        <edge id=\"10005\" source=\"2\" target=\"106\" label=\"on\"></edge>        <edge id=\"10006\" source=\"3\" target=\"107\" label=\"on\"></edge>        <edge id=\"10007\" source=\"3\" target=\"108\" label=\"on\"></edge>        <edge id=\"10008\" source=\"3\" target=\"109\" label=\"on\"></edge>        <edge id=\"10009\" source=\"3\" target=\"110\" label=\"on\"></edge>        <edge id=\"10010\" source=\"4\" target=\"111\" label=\"on\"></edge>        <edge id=\"10011\" source=\"4\" target=\"112\" label=\"on\"></edge>        <edge id=\"10012\" source=\"4\" target=\"113\" label=\"on\"></edge>        <edge id=\"10013\" source=\"5\" target=\"114\" label=\"on\"></edge>        <edge id=\"10014\" source=\"5\" target=\"115\" label=\"on\"></edge>        <edge id=\"10015\" source=\"5\" target=\"116\" label=\"on\"></edge>        <edge id=\"10016\" source=\"6\" target=\"117\" label=\"on\"></edge>        <edge id=\"10017\" source=\"6\" target=\"118\" label=\"on\"></edge>        <edge id=\"10018\" source=\"6\" target=\"119\" label=\"on\"></edge>        <edge id=\"11000\" source=\"101\" target=\"107\" label=\"link\"></edge>         <edge id=\"11003\" source=\"105\" target=\"111\" label=\"link\"></edge>        <edge id=\"11004\" source=\"107\" target=\"101\" label=\"link\"></edge>        <edge id=\"11005\" source=\"108\" target=\"112\" label=\"link\"></edge>        <edge id=\"11006\" source=\"109\" target=\"114\" label=\"link\"></edge>        <edge id=\"11007\" source=\"111\" target=\"105\" label=\"link\"></edge>        <edge id=\"11008\" source=\"112\" target=\"108\" label=\"link\"></edge>        <edge id=\"11009\" source=\"113\" target=\"117\" label=\"link\"></edge>        <edge id=\"11010\" source=\"114\" target=\"109\" label=\"link\"></edge>        <edge id=\"11011\" source=\"115\" target=\"118\" label=\"link\"></edge>        <edge id=\"11012\" source=\"117\" target=\"113\" label=\"link\"></edge>        <edge id=\"11013\" source=\"118\" target=\"115\" label=\"link\"></edge>        <edge id=\"12000\" source=\"103\" target=\"1000\" label=\"host\"></edge>        <edge id=\"12001\" source=\"103\" target=\"1001\" label=\"host\"></edge>        <edge id=\"12002\" source=\"110\" target=\"1002\" label=\"host\"></edge>        <edge id=\"12003\" source=\"116\" target=\"1003\" label=\"host\"></edge>        <edge id=\"12004\" source=\"106\" target=\"1004\" label=\"host\"></edge>        <edge id=\"12005\" source=\"119\" target=\"1005\" label=\"host\"></edge>      </graph>    </graphml>
\ No newline at end of file
+<?xml version=\"1.0\" ?><graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\">    <key id=\"id\" for=\"node\" attr.name=\"id\" attr.type=\"string\"></key>    <key id=\"type\" for=\"node\" attr.name=\"type\" attr.type=\"string\"></key>    <key id=\"dpid\" for=\"node\" attr.name=\"dpid\" attr.type=\"string\"></key>    <key id=\"desc\" for=\"node\" attr.name=\"desc\" attr.type=\"string\"></key>    <key id=\"number\" for=\"node\" attr.name=\"number\" attr.type=\"int\"></key>    <key id=\"dl_add\" for=\"node\" attr.name=\"dl_addr\" attr.type=\"string\"></key>    <key id=\"nw_addr\" for=\"node\" attr.name=\"nw_addr\" attr.type=\"string\"></key>    <key id=\"id\" for=\"edge\" attr.name=\"id\" attr.type=\"string\"></key>    <key id=\"source\" for=\"edge\" attr.name=\"source\" attr.type=\"string\"></key>    <key id=\"target\" for=\"edge\" attr.name=\"target\" attr.type=\"string\"></key>    <key id=\"label\" for=\"edge\" attr.name=\"label\" attr.type=\"string\"></key>    <graph id=\"G\" edgedefault=\"directed\">        <node id=\"1\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:01</data>            <data key=\"desc\">OpenFlow Switch at SEA</data>        </node>        <node id=\"2\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:02</data>            <data key=\"desc\">OpenFlow Switch at LAX</data>        </node>        <node id=\"3\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:03</data>            <data key=\"desc\">OpenFlow Switch at CHI</data>        </node>        <node id=\"4\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:04</data>            <data key=\"desc\">OpenFlow Switch at IAH</data>        </node>        <node id=\"5\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:05</data>            <data key=\"desc\">OpenFlow Switch at NYC</data>        </node>        <node id=\"6\">            <data key=\"type\">switch</data>            <data key=\"dpid\">00:00:00:00:00:00:0a:06</data>            <data key=\"desc\">OpenFlow Switch at ATL</data>        </node>        <node id=\"100\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at SEA Switch</data>        </node>        <node id=\"101\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at SEA Switch</data>        </node>        <node id=\"102\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at SEA Switch</data>        </node>        <node id=\"103\">            <data key=\"type\">port</data>            <data key=\"number\">4</data>            <data key=\"desc\">port 4 at SEA Switch</data>        </node>        <node id=\"104\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at LAX Switch</data>        </node>        <node id=\"105\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at LAX Switch</data>        </node>        <node id=\"106\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at LAX Switch</data>        </node>        <node id=\"107\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at CHI Switch</data>        </node>        <node id=\"108\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at CHI Switch</data>        </node>        <node id=\"109\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at CHI Switch</data>        </node>        <node id=\"110\">            <data key=\"type\">port</data>            <data key=\"number\">4</data>            <data key=\"desc\">port 4 at CHI Switch</data>        </node>        <node id=\"111\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at IAH Switch</data>        </node>        <node id=\"112\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at IAH Switch</data>        </node>        <node id=\"113\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at IAH Switch</data>        </node>        <node id=\"114\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at NYC Switch</data>        </node>        <node id=\"115\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at NYC Switch</data>        </node>        <node id=\"116\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at NYC Switch</data>        </node>        <node id=\"117\">            <data key=\"type\">port</data>            <data key=\"number\">1</data>            <data key=\"desc\">port 1 at ATL Switch</data>        </node>        <node id=\"118\">            <data key=\"type\">port</data>            <data key=\"number\">2</data>            <data key=\"desc\">port 2 at ATL Switch</data>        </node>        <node id=\"119\">            <data key=\"type\">port</data>            <data key=\"number\">3</data>            <data key=\"desc\">port 3 at ATL Switch</data>        </node>        <node id=\"1000\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">20:c9:d0:4a:e1:73</data>            <data key=\"nw_addr\">192.168.10.101</data>        </node>        <node id=\"1001\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">20:c9:d0:4a:e1:62</data>            <data key=\"nw_addr\">192.168.20.101</data>        </node>        <node id=\"1002\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">10:40:f3:e6:8d:55</data>            <data key=\"nw_addr\">192.168.10.1</data>        </node>        <node id=\"1003\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">a0:b3:cc:9c:c6:88</data>            <data key=\"nw_addr\">192.168.20.1</data>        </node>        <node id=\"1004\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">00:04:20:e2:50:a2</data>            <data key=\"nw_addr\">192.168.30.1</data>        </node>        <node id=\"1005\">            <data key=\"type\">device</data>            <data key=\"dl_addr\">58:55:ca:c4:1b:a0</data>            <data key=\"nw_addr\">192.168.40.1</data>        </node>        <edge id=\"10000\" source=\"1\" target=\"101\" label=\"on\"></edge>        <edge id=\"10001\" source=\"1\" target=\"102\" label=\"on\"></edge>        <edge id=\"10002\" source=\"1\" target=\"103\" label=\"on\"></edge>        <edge id=\"10003\" source=\"2\" target=\"104\" label=\"on\"></edge>        <edge id=\"10004\" source=\"2\" target=\"105\" label=\"on\"></edge>        <edge id=\"10005\" source=\"2\" target=\"106\" label=\"on\"></edge>        <edge id=\"10006\" source=\"3\" target=\"107\" label=\"on\"></edge>        <edge id=\"10007\" source=\"3\" target=\"108\" label=\"on\"></edge>        <edge id=\"10008\" source=\"3\" target=\"109\" label=\"on\"></edge>        <edge id=\"10009\" source=\"3\" target=\"110\" label=\"on\"></edge>        <edge id=\"10010\" source=\"4\" target=\"111\" label=\"on\"></edge>        <edge id=\"10011\" source=\"4\" target=\"112\" 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</graphml>