diff --git a/src/main.cpp b/src/main.cpp
index f6c7a91..223b02b 100755
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -539,36 +539,43 @@ int main(int argc, char *argv[]) {
        batch_size = std::stoi(opt_batch);
     
     if (use_postgres) {
-    std::cout << "Importing Models and Exploits into Database: ";
-    import_models(parsednm, parsedxp); //directly use the strings parsednm and parsedxp as SQL commands
-    gettimeofday(&tf3,NULL);
-    double tdiff3=(tf3.tv_sec-ts3.tv_sec)*1000.0+(tf3.tv_usec-ts3.tv_usec)/1000.0;
-    std::cout << "Done\n";
-    printf("------>The time to load .nm and .xp into the database took %lf ms.<------\n",tdiff3);
-    printf("\n");
+        std::cout << "Importing Models and Exploits into Database: ";
+        import_models(parsednm, parsedxp); //directly use the strings parsednm and parsedxp as SQL commands
+        gettimeofday(&tf3,NULL);
+        double tdiff3=(tf3.tv_sec-ts3.tv_sec)*1000.0+(tf3.tv_usec-ts3.tv_usec)/1000.0;
+        std::cout << "Done\n";
+        printf("------>The time to load .nm and .xp into the database took %lf ms.<------\n",tdiff3);
+        printf("\n");
     }
-    
+
     //------------------------------------------
     //program block 3:
     //------------------------------------------
 
     AGGenInstance _instance;
     //the following five assignments to _instance's members are all from db_function.cpp
-    _instance.facts = fetch_facts();
-    //The above function call returned an Keyvalue object and assigned the object to facts. The object mainly contains hash table and string vector based on all initial property and value.
-    //the following 4 lines can be used to check the content of the facts. It is based on the initial property and value from table quality, postcondition and topology.
-    //for(std::string abc: _instance.facts.get_str_vector()){
-      //  std::cout<<"Fact: "<<abc<<"\n";
-        //std::cout<<"Hash number: "<<_instance.facts[abc]<<"\n";
-        //std::cout<<"Operator: " <<abc[3]<<"\n";
-        //std::cout<<"Operator: " <<fetch_all_qualities(_instance.facts).get_op();
-    //}
-    _instance.initial_qualities = fetch_all_qualities(_instance.facts);  //prepare all the initial qualities, return a Quality vector of (quality plus facts)
-    _instance.initial_topologies = fetch_all_topologies(_instance.facts); //prepare all the initial topologies, return a Topology vector of (topology plus facts)
-    _instance.assets = fetch_all_assets(_instance.facts); //fetch each asset name and its related qualities. 
-    _instance.exploits = fetch_all_exploits(); //fetch each exploit and its precondition and post conditions from initial exploits
-    auto ex = fetch_all_exploits(); //make a copy of initial exploits
-
+    //the following five assignments are only applicable when use_postgres is set to true
+    if (use_postgres) {
+        _instance.facts = fetch_facts();
+        //The above function call returned an Keyvalue object and assigned the object to facts. The object mainly contains hash table and string vector based on all initial property and value.
+        //the following 4 lines can be used to check the content of the facts. It is based on the initial property and value from table quality, postcondition and topology.
+        //for(std::string abc: _instance.facts.get_str_vector()){
+        //  std::cout<<"Fact: "<<abc<<"\n";
+            //std::cout<<"Hash number: "<<_instance.facts[abc]<<"\n";
+            //std::cout<<"Operator: " <<abc[3]<<"\n";
+            //std::cout<<"Operator: " <<fetch_all_qualities(_instance.facts).get_op();
+        //}
+        _instance.initial_qualities = fetch_all_qualities(_instance.facts);  //prepare all the initial qualities, return a Quality vector of (quality plus facts)
+        _instance.initial_topologies = fetch_all_topologies(_instance.facts); //prepare all the initial topologies, return a Topology vector of (topology plus facts)
+        _instance.assets = fetch_all_assets(_instance.facts); //fetch each asset name and its related qualities. 
+        _instance.exploits = fetch_all_exploits(); //fetch each exploit and its precondition and post conditions from initial exploits
+        auto ex = fetch_all_exploits(); //make a copy of initial exploits
+    }
+    else {
+        std::cout << parsednm << std::endl;
+        std::cout << "Not yet implemented." << std::endl;
+        return(1);
+    }
     std::cout << "Assets: " << _instance.assets.size() << "\n"; //# of assets, vector size
     std::cout << "Exploits: " << _instance.exploits.size() << "\n"; //# of exploits, vector size
     std::cout << "Facts: " << _instance.facts.size() << "\n"; //how many different parameters and values are there? class size() method