Adding a new index to existing table - will this skip indexing of current rows

[Shpadoinkle]

Just a question regarding adding a new index and with a new gsi pk and sk to an existing table. with composite values pointed at existing fields.

Does this apply a retroactive application of these values to the existing rows? or will they be lost/excludes from the new queries on this index?

[raryanpur]

@Shpadoinkle it's automatic (DynamoDB handles this). See here, Phases of index creation -> Backfilling.