OptionalindexOptionalfilterOptionalprojectionOptionalexpressionOptionalexpressionOptionallimitOptionalexclusiveOptionalconsistentOptionalsegmentFor parallel scans: this segment's index (0-based).
OptionaltotalFor parallel scans: total number of segments.
Restricts which attributes are returned. Use
expressionAttributeNamesfor any#aliastokens referenced here (same rules asgetItem()).