Retrieve Data from DynamoDB if complete sort key not known-CodePudding

I am new to DyanmoDB. I am creating partition key and sort key when pushing data into DynamoDb but when i want to retrieve the data i have the partition key but not the complete sort key. I know the beginning of the sort key but not the complete key.

table.query(QueryEnhancedRequest.builder().queryConditional(QueryConditional.keyEqualTo(Key.builder().partitionValue("KEY#"   id).build())).build())

Below are the tables partition and sort key:

private static final String TEMPLATE = "%s#%s";    
@DynamoDbPartitionKey
      @Override
      public String getPk() {
        return String.format(TEMPLATE, "KEY", getId());
      }
    
      @DynamoDbSortKey
      @Override
      public String getSk() {
        return String.format(TEMPLATE, "KEY_SORT", getName());
      }

I used what i provided above but its showing this error: The provided key element does not match the schema (Service: DynamoDb, Status Code: 400, Request ID: response id)
After looking into the issue i found out that key should be the combination of partition and sort key. But the issue is i don't know the complete sort key for the second request.

CodePudding user response：

If you only know the beginning of the sort key, you can use BEGINS_WITH query.

aws dynamodb query \
    --table-name TABLE \
    --key-condition-expression "Id = :id and begins_with(Key, :key)" \
    --expression-attribute-values '{":id":{"S":"1"}, ":key":{"S":"KEY-BEGINNING"}}'

You need to provide the primary key and the beginning of the sort key for this query.

See Key condition expressions for query

CodePudding user response：

You need to use QueryConditional with sortBeginsWith():

For example, imagine you have the following information

partition key pk = "key#23456"

sort key sk begins with "abcd"

you are unsure of the remainder of the sort key:

        QueryConditional condition = QueryConditional.sortBeginsWith(
                Key.builder()
                        .partitionValue("key#23456")
                        .sortValue("abcd")
                        .build()
        );

        QueryEnhancedRequest request = QueryEnhancedRequest.builder()
                .queryConditional(condition)
                .build();


        table.query(request);