12. Query
• A Query operation directly accesses
items from a table using the table
primary key, , or from an index using the
index key.
• Example
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13. Scan
• The Scan operation returns one or more
items and item attributes by accessing
every item in the table.To have Amazon
DynamoDB return fewer items, you can
provide a ScanFilter.
• Example
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14. Query & Scan cost
• For Query, all items returned are treated as
a single read operation. As a result,
Amazon DynamoDB computes the total
size of all items and then rounds up to the
next 4 KB boundary.
• In the case of a Scan operation,Amazon
DynamoDB considers the size of the items
that are evaluated.
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