Function SelectByKey

be/src/exprs/string-functions.cc:160–170

Extract all the values for 'key' where objects in 'queue' contain that key. Replace the contents of queue with the values found.

// Extract all the values for 'key' where objects in 'queue' contain that key.
// Replace the contents of queue with the values found.
static void SelectByKey(const string& key, JsonUdfValue* queue,
    JsonUdfAllocator* allocator) {
  SizeType old_items = queue->Size();  // RapidJson uses SizeType instead of size_t
  JsonUdfValue item;
  for (SizeType i = 0; i < old_items; ++i) {
    item = (*queue)[i];
    if (!item.IsObject() || !item.HasMember(key)) continue;
    queue->PushBack(item[key], *allocator);
  }
  queue->Erase(queue->Begin(), queue->Begin() + old_items);
}

// Extract all the values for 'index' where arrays in 'queue' contain that index.
// Replace the contents of queue with the values found.