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Data in a data store can be updated through two different paths. The first is by giving a key-value pair for a domain by raising wrangler:ds_update and then responding to wrangler:ds_updated. The second is by changing all the key-value mappings under a domain by raising wrangler:ds_assign_map_to_domain with a new key-value map and reacting to wrangler:ds_domain_updated. It is recommended to use the latter way of updating sparingly, such as for data migration purposes.
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