dynamodb batchupdate using DynamoDBMapper

Question

As per

http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_BatchWriteItem.html d

Dynamodb does not support batchupdate only batchwrite/put is supported . But DynamoDBMapper supports batchWrite with a behaviour of UPDATE_SKIP_NULL_ATTRIBUTES. Does it mean internally mapper calls single single update instead of batchupdate for UPDATE_SKIP_NULL_ATTRIBUTES ?

Ashan · Accepted Answer · 2017-08-24 19:03:48Z

2

When you use BatchWrite, it replaces the existing items(Not update). Even if you use DynamoDBMapper, the functionality should be the same.

According to the DynamoDBMapper source code, SaveBehavior with UPDATE_SKIP_NULL_ATTRIBUTES, it ultimately calls BatchWriteItemRequest iteratively in 25 batch size, which replaces the existing items.

Check the following statement in AWS Class Reference Documentation.

NOTE: BatchWriteItem cannot update items. To update items, use the UpdateItem API.

edited Aug 24, 2017 at 19:03

answered Aug 24, 2017 at 18:15

Ashan

19.7k5 gold badges53 silver badges69 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user1846749 Over a year ago

by default yes it replaces but when you set in DynamoDBMapperConfig withSaveBehavior(SaveBehavior.UPDATE_SKIP_NULL_ATTRIBUTES) then also does it replaces existing item or skip the null attributes ?

Ashan Over a year ago

Check the updated answer :), I just gone through the source code and checked whats happening internally.

Collectives™ on Stack Overflow

dynamodb batchupdate using DynamoDBMapper

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related