Dynamodb Query Multiple Keys
It allows you to select multiple items that have the same partition hash key but different sort range keys.
Dynamodb query multiple keys. Consider using filter expressions you will probably end up using more read throughput filtering is performed after data is received from db than you need but get the desired results. In this lesson we ll learn some basics around the query operation including using queries to. Querying is a very powerful operation in dynamodb. Although filtering is done on the server side before results are sent back the read costs are calculated on the query operation before the filter is applied.
You can t use the query method on a table without specifying a specific hash key. The query operation enables you to query a table or a secondary index in amazon dynamodb. If the table or index has a sort key you can refine the results by providing a sort key value and a condition. Is there a way to query multiple hash keys using a single query in amazon s aws sdk for java.
The method to use instead is scan. Optionally you can provide a sort key attribute and use a comparison operator to refine the search results. 2 ahh ok figured it out. Query returns all items with that partition key value.
Because you have multiple partition keys and your date ranges are different i m not aware of any way to satisfy this in one query. The hash and range keys allow for a one to many like structure for a single hash key there can be multiple range keys. The hash key is the status of a project ie. Scan dynamodb query multiple keys python.
You can potentially make the queries in parallel however as they potentially hit different partitions and this will reduce your total latency. When thinking about how to set up our data structure think how you would fill in the blanks for the following query. New assigned processing or complete. You must provide the name of the partition key attribute and a single value for that attribute.
The range key is a set of project ids. In this post we discuss an alternative approach to querying on multiple attributes in dynamodb which is to concatenate attributes on a key. Retrieve all items from dynamodb using query. Jarmod apr 21 at 12 26.
However you must use some forethought. The query operation in amazon dynamodb finds items based on primary key values. You must provide a partition key value and an equality condition. But you will not be able to build query with multiple range keys simultaneously because dynamodb can only use one index at a time.
So if i replace. Even adding a gsi won t help. The hash key is particularly important you can only grab data for a single hash key in a query operation. Retrieve all items with a given partition key.
With this pattern you can query to retrieve a full document history with begins with v as shown in the following screenshot.