Function SelectByIndex

be/src/exprs/string-functions.cc:174–184

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

// Extract all the values for 'index' where arrays in 'queue' contain that index.
// Replace the contents of queue with the values found.
static void SelectByIndex(const int index, JsonUdfValue* queue,
    JsonUdfAllocator* allocator) {
  DCHECK(queue->IsArray());
  SizeType old_items = queue->Size();
  for (SizeType i = 0; i < old_items; ++i) {
    JsonUdfValue& item = (*queue)[i];
    if (!item.IsArray() || index >= item.Capacity()) continue;
    queue->PushBack(item[index], *allocator);
  }
  queue->Erase(queue->Begin(), queue->Begin() + old_items);
}

// Expand all arrays in the queue and replace the contents of queue with them.
static void ExpandArrays(JsonUdfValue* queue, JsonUdfAllocator* allocator) {