Partial for for lp bug 796647 - handle DELETED records in ha_rnd_next of backing table

3 files changed, 22 insertions, 15 deletions

diff --git a/storage/oqgraph/graphcore.cc b/storage/oqgraph/graphcore.cc
index ce785b205c3..0b6be1da6af 100644
--- a/storage/oqgraph/graphcore.cc
+++ b/storage/oqgraph/graphcore.cc
@@ -1111,8 +1111,18 @@ int edges_cursor::fetch_row(const row &row_info, row &result,
   {
     result= row_info;
     result.orig_indicator= result.dest_indicator= result.weight_indicator= 1;
-    result.orig= get(boost::vertex_index, share->g, source( *edge, share->g ) );
-    result.dest= get(boost::vertex_index, share->g, target( *edge, share->g ) );
+
+    oqgraph3::vertex_id orig = get(boost::vertex_index, share->g, source( *edge, share->g ) );
+    oqgraph3::vertex_id dest = get(boost::vertex_index, share->g, target( *edge, share->g ) );
+
+    // bug 796647c - may be symptomatic of a bigger problem with representation
+    // but origid and destid can be -1 indicating no such record, NULL? but oqgraph3::vertex_id
+    // seems to resolve to VertexID (unsigned) in row
+    // in any case we should check for errors (-1) in origid... because all edges have at least one vertex by definition
+    assert( ! ((size_t)orig == (size_t)-1 && (size_t)dest == (size_t)-1)); // indicates we havent handle a HA_ERR_RECORD_DELETED somewhere
+
+    result.orig= orig;
+    result.dest= dest;
     result.weight= get(boost::edge_weight, share->g, *edge);
     return oqgraph::OK;
   }
diff --git a/storage/oqgraph/ha_oqgraph.cc b/storage/oqgraph/ha_oqgraph.cc
index 8cd15dec2e8..5251d1600eb 100644
--- a/storage/oqgraph/ha_oqgraph.cc
+++ b/storage/oqgraph/ha_oqgraph.cc
@@ -1050,7 +1050,7 @@ int ha_oqgraph::fill_record(byte *record, const open_query::row &row)
 
 int ha_oqgraph::rnd_init(bool scan)
 {
-  edges->file->info(HA_STATUS_VARIABLE); // Fix for bug 1195735 - ensure we operate with up to date count!
+  edges->file->info(HA_STATUS_VARIABLE); // Fix for bug 1195735, hang after truncate table - ensure we operate with up to date count
   edges->prepare_for_position();
   return error_code(graph->random(scan));
 }
@@ -1060,14 +1060,7 @@ int ha_oqgraph::rnd_next(byte *buf)
   int res;
   open_query::row row = {};
 
-  // Problem: bug 1195735 - mysqld hang if we delete * from the underlying table, we get an infinite loop through here
-  // fetch_row() --> fetch_row() --> num_edges() --> _table->file->stats->records
-  // _table is actually a handle on the backing table we just deleted everything from.  so the statistics are out of date.
-  // so we really need to force a refresh on the backing store statistics, when starting a new query
-  // So we probably need to fix this bug in rnd_init
-  // Note, close() never called in between; this would otherwise clean things up
-
-  if (!(res= graph->fetch_row(row))) // FIXME - this called after DELETE FROM graph_base; hangs...
+  if (!(res= graph->fetch_row(row)))
     res= fill_record(buf, row);
   table->status= res ? STATUS_NOT_FOUND: 0;
   return error_code(res);
diff --git a/storage/oqgraph/oqgraph_thunk.cc b/storage/oqgraph/oqgraph_thunk.cc
index d8e05f04af1..8e5cf2f0de7 100644
--- a/storage/oqgraph/oqgraph_thunk.cc
+++ b/storage/oqgraph/oqgraph_thunk.cc
@@ -235,7 +235,7 @@ int oqgraph3::cursor::restore_position()
 }
 
 oqgraph3::vertex_id oqgraph3::cursor::get_origid()
-{
+{ 
   if (_origid)
     return *_origid;
 
@@ -509,10 +509,14 @@ int oqgraph3::cursor::seek_to(
   }
   else
   {
-    if (int rc= table.file->ha_rnd_init(true))
+    int rc;
+    if ((rc= table.file->ha_rnd_init(true)))
       return clear_position(rc);
-    if (int rc= table.file->ha_rnd_next(table.record[0]))
-    {
+
+    // We need to skip over any deleted records we encounter. Bug 796647
+    while ( ((rc= table.file->ha_rnd_next(table.record[0]))) != 0) {
+      if (rc == HA_ERR_RECORD_DELETED)
+        continue;
       table.file->ha_rnd_end();
       return clear_position(rc);
     }