What is the main difference between key-value and wide column? Is it that all data from a given column is stored together, which makes reads of specific columns faster?
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With a key-value nosql db, every key only maps to one value. With a wide-column nosql db, every key maps to potentially many columns that can be selected. This can make reads more efficient, since we only need to read the columns that we are interested in. With the key-value nosql db, all the columns would be in the same value field, so everything would have to be read.
Dewey Munoz
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So is DynamoDB actually a wide-column store that only has the query capacities of document-store unless the fields are indexed? This answer says DynamoDB is ""wide-column"", but could not query unindexed fields without reading the whole record: https://stackoverflow.com/a/65067047/7053488 – Zack Light Dec 01 '22 at 12:47
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A wide-column store is like a 2-dimensional key-value store, where the first key is used as a row identifier and the second is used as a column identifier.
Carole Nash
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