Function sp_io::default_child_storage::storage_kill

pub fn storage_kill(storage_key: &[u8], limit: Option<u32>) -> bool

Clear a child storage key.

Deletes all keys from the overlay and up to limit keys from the backend if it is set to Some. No limit is applied when limit is set to None.

The limit can be used to partially delete a child trie in case it is too large to delete in one go (block).

It returns false iff some keys are remaining in the child trie after the functions returns.

Note

Please note that keys that are residing in the overlay for that child trie when issuing this call are all deleted without counting towards the limit. Only keys written during the current block are part of the overlay. Deleting with a limit mostly makes sense with an empty overlay for that child trie.

Calling this function multiple times per block for the same storage_key does not make much sense because it is not cumulative when called inside the same block. Use this function to distribute the deletion of a single child trie across multiple blocks.