.

lib/zawgl-core/src/graph_engine/mod.rs

@@ -245,6 +245,10 @@ impl GraphEngine {
     pub fn sync(&mut self) {
         self.repository.sync();
     }
+
+    pub fn clear(&mut self) {
+        self.repository.clear();
+    }
 }
 
 

lib/zawgl-core/src/repository/graph_repository.rs

@@ -261,6 +261,13 @@ impl GraphRepository {
         self.properties_repository.sync();
         self.labels_store.sync();
     }
+    pub fn clear(&mut self) {
+        self.nodes_labels_index.clear();
+        self.relationships_store.clear();
+        self.nodes_store.clear();
+        self.properties_repository.clear();
+        self.labels_store.clear();
+    }
 }
 
 #[derive(Copy, Clone)]

lib/zawgl-core/src/repository/index/b_tree.rs

@@ -234,6 +234,9 @@ impl BTreeIndex {
     pub fn soft_sync(&mut self) {
         self.node_store.soft_sync();
     }
+    pub fn clear(&mut self) {
+        self.node_store.clear();
+    }
 }
 
 #[cfg(test)]

lib/zawgl-core/src/repository/index/store/mod.rs

@@ -589,12 +589,15 @@ impl BTreeNodeStore {
 
     pub fn sync(&mut self) {
         self.records_manager.lock().unwrap().sync();
-        self.pool.clear();
-        self.nodes_pool.clear();
+        self.clear();
     }
     pub fn soft_sync(&mut self) {
         self.records_manager.lock().unwrap().sync();
     }
+    pub fn clear(&mut self) {
+        self.pool.clear();
+        self.nodes_pool.clear();
+    }
 }
 
 struct BTreeNodePool {
@@ -634,7 +637,7 @@ impl BTreeNodePool {
         self.nodes_map.get(id).and_then(|pos| self.nodes.get(*pos).map(|n| n.clone()))
     }
 
-    fn clear(&mut self) {
+    pub fn clear(&mut self) {
         self.nodes_map.clear();
         self.nodes.clear();
     }

lib/zawgl-core/src/repository/properties_repository.rs

@@ -239,6 +239,11 @@ impl PropertiesRespository {
     pub fn sync(&mut self) {
         self.prop_store.sync();
         self.dyn_store.sync();
+
+    }
+    pub fn clear(&mut self) {
+        self.prop_store.clear();
+        self.dyn_store.clear();
     }
 }
 

lib/zawgl-core/src/repository/records/mod.rs

@@ -474,6 +474,9 @@ impl RecordsManager {
         self.pager.sync();
     }
 
+    pub fn clear(&mut self) {
+        self.pager.clear();
+    }
     pub fn retrieve_all_records_ids(&mut self) -> RecordsManagerResult<Vec<u64>> {
         let page_count = self.pager.get_header_page_ref().get_page_count();
         let nb_records_per_page = self.page_map.nb_records_per_page;

lib/zawgl-core/src/repository/store/dynamic_store.rs

@@ -101,6 +101,10 @@ impl DynamicStore {
     pub fn sync(&mut self) {
         self.records_manager.sync();
     }
+
+    pub fn clear(&mut self) {
+        self.records_manager.clear();
+    }
 }
 
 #[cfg(test)]

lib/zawgl-core/src/repository/store/nodes_store.rs

@@ -48,6 +48,9 @@ impl NodesStore {
     pub fn retrieve_all_nodes_ids(&mut self) -> Option<Vec<u64>> {
         self.records_manager.retrieve_all_records_ids().ok()
     }
+    pub fn clear(&mut self) {
+        self.records_manager.clear();
+    }
 }
 
 #[cfg(test)]

lib/zawgl-core/src/repository/store/properties_store.rs

@@ -40,5 +40,9 @@ impl PropertiesStore {
     }
     pub fn sync(&mut self) {
         self.records_manager.sync();
+        self.clear();
+    }
+    pub fn clear(&mut self) {
+        self.records_manager.clear();
     }
 }

lib/zawgl-core/src/repository/store/relationships_store.rs

@@ -44,6 +44,9 @@ impl RelationshipsStore {
     pub fn sync(&mut self) {
         self.records_manager.sync();
     }
+    pub fn clear(&mut self) {
+        self.records_manager.clear();
+    }
 }
 
 

lib/zawgl-front/src/lib.rs

@@ -49,7 +49,10 @@ pub fn handle_open_cypher_request(tx_handler: TxHandler, graph_request_handler:
                 Ok(mg) => {
                     build_response(request_id, mg, &r)
                 },
-                Err(e) => build_error(request_id, e),
+                Err(e) => {
+                    graph_request_handler.lock().unwrap().cancel();
+                    build_error(request_id, e)
+                },
             }
         },
         Err(ce) => build_cypher_error(request_id, ce),

lib/zawgl-front/src/tx_handler/request_handler.rs

@@ -31,7 +31,7 @@ use zawgl_cypher_query_model::QueryStep;
 use crate::planner::handle_query_steps;
 
 use crate::tx_handler::tx_context::TxContext;
-use super::{DatabaseError};
+use super::DatabaseError;
 
 
 pub type RequestHandler = Arc<Mutex<GraphRequestHandler>>;
@@ -78,6 +78,10 @@ impl <'a> GraphRequestHandler {
         Ok(Vec::new())
     }
 
+    pub fn cancel(&mut self) {
+        self.graph_engine.clear();
+    }
+
     fn _commit_tx(&mut self, session_id: &str) {
         let graph_engine = self.map_session_graph_engine.get_mut(session_id);
         if let Some(ge) = graph_engine {