diff --git a/arangod/Aql/ExecutionBlock.h b/arangod/Aql/ExecutionBlock.h
index fac2afa890..c5633a2e0d 100644
--- a/arangod/Aql/ExecutionBlock.h
+++ b/arangod/Aql/ExecutionBlock.h
@@ -189,12 +189,11 @@ namespace triagens {
 ////////////////////////////////////////////////////////////////////////////////
 
         ExecutionBlock* operator[] (size_t pos) {
-          if (pos > _dependencies.size()) {
+          if (pos >= _dependencies.size()) {
             return nullptr;
           }
-          else {
-            return _dependencies.at(pos);
-          }
+
+          return _dependencies.at(pos);
         }
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/arangod/Aql/ExecutionNode.h b/arangod/Aql/ExecutionNode.h
index 7b5673bb93..6fc667a4b7 100644
--- a/arangod/Aql/ExecutionNode.h
+++ b/arangod/Aql/ExecutionNode.h
@@ -172,12 +172,11 @@ namespace triagens {
 ////////////////////////////////////////////////////////////////////////////////
 
         ExecutionNode* operator[] (size_t pos) const {
-          if (pos > _dependencies.size()) {
+          if (pos >= _dependencies.size()) {
             return nullptr;
           }
-          else {
-            return _dependencies.at(pos);
-          }
+
+          return _dependencies.at(pos);
         }
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/arangod/Aql/Query.cpp b/arangod/Aql/Query.cpp
index 881e55c02a..d56f47a349 100644
--- a/arangod/Aql/Query.cpp
+++ b/arangod/Aql/Query.cpp
@@ -238,9 +238,15 @@ QueryResult Query::execute () {
   catch (triagens::arango::Exception const& ex) {
     return QueryResult(ex.code(), ex.message());
   }
-  catch (...) {
+  catch (std::bad_alloc const& ex) {
     return QueryResult(TRI_ERROR_OUT_OF_MEMORY, TRI_errno_string(TRI_ERROR_OUT_OF_MEMORY));
   }
+  catch (std::exception const& ex) {
+    return QueryResult(TRI_ERROR_INTERNAL, ex.what());
+  }
+  catch (...) {
+    return QueryResult(TRI_ERROR_INTERNAL, TRI_errno_string(TRI_ERROR_INTERNAL));
+  }
 }
 
 ////////////////////////////////////////////////////////////////////////////////