diff --git a/src/postgresqlconnector.cpp b/src/postgresqlconnector.cpp
index 4517268..f882554 100644
--- a/src/postgresqlconnector.cpp
+++ b/src/postgresqlconnector.cpp
@@ -93,31 +93,32 @@ bool PostgreSQLConnector::do_query(const char * query_str, PostgreSQLQueryResult
 {
 	if( pg_conn && psql_result )
 	{
+		psql_result->clear();
+
 		if( log_queries && logger )
 		{
 			(*logger) << PT::Logger::log1 << "Db: executing query: " << query_str << PT::Logger::logend << PT::Logger::logsave;
 		}
 
-		psql_result->result = PQexec(pg_conn, query_str);
+		psql_result->psql_result = PQexec(pg_conn, query_str);
 
-		if( !psql_result->result )
+		if( !psql_result->psql_result )
 		{
 			if( PQstatus(pg_conn) != CONNECTION_OK )
 			{
 				assert_connection();
-				psql_result->result = PQexec(pg_conn, query_str);
+				psql_result->psql_result = PQexec(pg_conn, query_str);
 			}
 		}
 
-		if( psql_result->result )
+		if( psql_result->psql_result )
 		{
-			psql_result->status = PQresultStatus(psql_result->result);
-			psql_result->result_rows = static_cast<size_t>(PQntuples(psql_result->result));
+			psql_result->psql_status = PQresultStatus(psql_result->psql_result);
+			psql_result->result_rows = static_cast<size_t>(PQntuples(psql_result->psql_result));
 		}
 
-		if( !psql_result->result || psql_result->status == PGRES_FATAL_ERROR )
+		if( !psql_result->psql_result || psql_result->psql_status == PGRES_FATAL_ERROR )
 		{
-			psql_result->was_error = true;
 			const char * err_msg = PQerrorMessage(pg_conn);
 
 			if( err_msg )
@@ -133,9 +134,13 @@ bool PostgreSQLConnector::do_query(const char * query_str, PostgreSQLQueryResult
 					(*logger) << PT::Logger::log1 << "Db: " << err_msg << PT::Logger::logend << PT::Logger::logsave;
 			}
 		}
+		else
+		{
+			psql_result->status = true;
+		}
 	}
 
-	return (psql_result && psql_result->result != nullptr);
+	return (pg_conn && psql_result && psql_result->psql_result != nullptr && psql_result->status);
 }
 
 
@@ -210,7 +215,8 @@ bool PostgreSQLConnector::query_select(const char * query_str, QueryResult & que
 
 	if( psql_result )
 	{
-		result = (do_query(query_str, psql_result) && psql_result->status == PGRES_TUPLES_OK);
+		result = (do_query(query_str, psql_result) && psql_result->psql_status == PGRES_TUPLES_OK);
+		psql_result->status = result;
 	}
 
 	return result;
@@ -224,7 +230,8 @@ bool PostgreSQLConnector::query_update(const char * query_str, QueryResult & que
 
 	if( psql_result )
 	{
-		result = (do_query(query_str, psql_result) && psql_result->status == PGRES_COMMAND_OK);
+		result = (do_query(query_str, psql_result) && psql_result->psql_status == PGRES_COMMAND_OK);
+		psql_result->status = result;
 	}
 
 	return result;
@@ -238,7 +245,8 @@ bool PostgreSQLConnector::query_insert(const char * query_str, QueryResult & que
 
 	if( psql_result )
 	{
-		result = (do_query(query_str, psql_result) && psql_result->status == PGRES_COMMAND_OK);
+		result = (do_query(query_str, psql_result) && psql_result->psql_status == PGRES_COMMAND_OK);
+		psql_result->status = result;
 	}
 
 	return result;
@@ -252,7 +260,8 @@ bool PostgreSQLConnector::query_remove(const char * query_str, QueryResult & que
 
 	if( psql_result )
 	{
-		result = (do_query(query_str, psql_result) && psql_result->status == PGRES_COMMAND_OK);
+		result = (do_query(query_str, psql_result) && psql_result->psql_status == PGRES_COMMAND_OK);
+		psql_result->status = result;
 	}
 
 	return result;
diff --git a/src/postgresqlqueryresult.cpp b/src/postgresqlqueryresult.cpp
index f23eed1..0489d58 100644
--- a/src/postgresqlqueryresult.cpp
+++ b/src/postgresqlqueryresult.cpp
@@ -42,20 +42,20 @@ namespace morm
 
 PostgreSQLQueryResult::PostgreSQLQueryResult()
 {
-	result = nullptr;
-	status = PGRES_EMPTY_QUERY;
+	psql_result = nullptr;
+	psql_status = PGRES_EMPTY_QUERY;
 }
 
 
 void PostgreSQLQueryResult::clear()
 {
-	if( result )
+	if( psql_result )
 	{
-		PQclear(result);
+		PQclear(psql_result);
 	}
 
-	result = nullptr;
-	status = PGRES_EMPTY_QUERY;
+	psql_result = nullptr;
+	psql_status = PGRES_EMPTY_QUERY;
 
 	QueryResult::clear();
 }
@@ -63,7 +63,7 @@ void PostgreSQLQueryResult::clear()
 
 bool PostgreSQLQueryResult::has_db_result()
 {
-	return result != nullptr;
+	return psql_result != nullptr;
 }
 
 
@@ -71,15 +71,15 @@ const char * PostgreSQLQueryResult::get_field_string_value(const char * column_n
 {
 	const char * value_str = nullptr;
 
-	if( result )
+	if( psql_result )
 	{
-		int col_index = PQfnumber(result, column_name);
+		int col_index = PQfnumber(psql_result, column_name);
 
 		if( col_index != -1 )
 		{
 			if( cur_row < result_rows )
 			{
-				value_str = PQgetvalue(result, cur_row, col_index);
+				value_str = PQgetvalue(psql_result, cur_row, col_index);
 			}
 		}
 	}
@@ -93,9 +93,9 @@ int PostgreSQLQueryResult::get_column_index(const char * column_name)
 {
 	int col_index = -1;
 
-	if( result )
+	if( psql_result )
 	{
-		col_index = PQfnumber(result, column_name);
+		col_index = PQfnumber(psql_result, column_name);
 		// returns -1 if there is no such a column
 	}
 
@@ -108,10 +108,10 @@ const char * PostgreSQLQueryResult::get_value_from_result(int row, int col)
 {
 	const char * value_str = nullptr;
 
-	if( result )
+	if( psql_result )
 	{
-		value_str = PQgetvalue(result, row, col);
-		// can return a null pointer if there is no such an item in the last result
+		value_str = PQgetvalue(psql_result, row, col);
+		// can return a null pointer if there is no such an item in the last psql_result
 	}
 
 	return value_str;
@@ -122,9 +122,9 @@ int PostgreSQLQueryResult::get_value_length(int row, int col)
 {
 	int len = 0;
 
-	if( result )
+	if( psql_result )
 	{
-		len = PQgetlength(result, row, col);
+		len = PQgetlength(psql_result, row, col);
 	}
 
 	return len;
@@ -135,9 +135,9 @@ bool PostgreSQLQueryResult::is_null(int row, int col)
 {
 	bool is_null = false;
 
-	if( result )
+	if( psql_result )
 	{
-		is_null = (PQgetisnull(result, row, col) == 1);
+		is_null = (PQgetisnull(psql_result, row, col) == 1);
 	}
 
 	return is_null;
diff --git a/src/postgresqlqueryresult.h b/src/postgresqlqueryresult.h
index 9f869c5..74c4dd5 100644
--- a/src/postgresqlqueryresult.h
+++ b/src/postgresqlqueryresult.h
@@ -46,8 +46,8 @@ namespace morm
 
 struct PostgreSQLQueryResult : public QueryResult
 {
-	PGresult * result;  // can be null
-	ExecStatusType status;
+	PGresult * psql_result;  // can be null
+	ExecStatusType psql_status;
 
 
 	PostgreSQLQueryResult();
diff --git a/src/queryresult.cpp b/src/queryresult.cpp
index 1304f35..b5bd092 100644
--- a/src/queryresult.cpp
+++ b/src/queryresult.cpp
@@ -57,7 +57,7 @@ void QueryResult::clear()
 {
 	result_rows = 0;
 	cur_row = 0;
-	was_error = false;
+	status = false;
 	error_msg.clear();
 
 	temp_column_name.clear();
diff --git a/src/queryresult.h b/src/queryresult.h
index 53e27c1..5caef0e 100644
--- a/src/queryresult.h
+++ b/src/queryresult.h
@@ -43,9 +43,9 @@ namespace morm
 
 struct QueryResult
 {
+	bool status;
 	size_t result_rows; // how many rows in the result query
 	size_t cur_row;		// used for reading
-	bool was_error;
 	std::wstring error_msg;
 
 	std::string temp_column_name;