* Use sqlite3_stmt_readonly to determine if sqlite3_changes should be called

* Remove sys.dual dependency, improving multi-threaded applications

Data/SQLite/src/SessionImpl.cpp

@@ -195,14 +195,6 @@ void SessionImpl::open(const std::string& connect)
 		throw ConnectionFailedException(ex.displayText());
 	}
 
-	if (SQLITE_OK != sqlite3_exec(_pDB,
-		"attach database ':memory:' as sys;"
-		"create table sys.dual (dummy);", 
-		0, 0, 0))
-	{
-		throw ExecutionException("Cannot create system database.");
-	}
-
 	_connected = true;
 }