@Override
    public ComplexEventChunk<StateEvent> tryUpdate(ComplexEventChunk<StateEvent> updatingOrAddingEventChunk,
                                                   Object storeEvents,
                                                   InMemoryCompiledUpdateSet compiledUpdateSet,
                                                   AddingStreamEventExtractor addingStreamEventExtractor) {

        updatingOrAddingEventChunk.reset();
        while (updatingOrAddingEventChunk.hasNext()) {
            StateEvent overwritingOrAddingEvent = updatingOrAddingEventChunk.next();
            ((IndexedEventHolder) storeEvents).overwrite(addingStreamEventExtractor.getAddingStreamEvent
                    (overwritingOrAddingEvent));

        }
        return null;
    }
Operator which is related to non-indexed In-memory table operations.
modules/siddhi-core/src/main/java/io/siddhi/core/util/collection/operator/OverwriteTableIndexOperator.java