If you want to grab just one specific one, you'd do a GetItem request on both the partition key and sort key. You would do a query operation on just the partition key, userId = 0515dc74. So the user with ID 0515dc74 logs in, and you want to show them all the gadgets they own. This is how you might structure it: userId (partition key) Thinking in terms of traditional databases, you might have the primary key be gadgetId, but in DynamoDB this is not correct. As a rudimentary example, let's say you have a database of gadgets, and each gadget is owned by a single user. This leads to the next question: how do you query a bunch of items instead of just a single item (partition key)? Your data may not be structured correctly. In 95% of the cases, you want to use query to list a bunch of things. It reads every single item in your table, which will wind up consuming your read capacity. I'm using pagination in my Vue app with AppSync, so maybe I can help with a couple things.įirst off, you hardly ever want to use the scan operation on DynamoDB. I'm no DynamoDB expert, but doesn't scanIndexForward simply reverse the list of results? So if your data comes back A-Z, scanIndexForward: false will make it come back Z-A. Operation "Scan" returns multiple items but it doesn't support "scanIndexForward" option.Īm I doing all right? Or is there another way to implement prev pagination?Īnd is it possible to implement pagination with the numbered pages not only previous/next ones? So when I'm specifying partitionKeyName = :partitionkeyval I'll getting only one item and I can't get multiple items because of "=" operator in "expression". PartitionKeyName = :partitionkeyval AND sortKeyName = :sortkeyvalĪs says DynamoDB reference. Following is an example, using the = comparison operator for the sort key:
If you also want to provide a condition for the sort key, it must be combined using AND with the condition for the sort key. The partition key equality test is required, and must be specified in the following format: And the troubles become here because in "expression" attribute you'll need set expression with the following condition:
This attribute works only with "Query" operation not with "Scan". When you want to get the previous "page" of your data you will need specify "scanIndexForward": false in your query to switch scan direction throw the data table. My resolvers are connected to the DynamoDB. But I've troubles with the backward paginating. I've decided to make a pagination in my app.
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