what will happen if we insert into dynamo DB with a duplicate …
2014年9月6日 · I am trying to insert into dynamo DB. When I call the putItem function what will happen if the hash key is already present in the DB?
What are the pros and cons of DynamoDB with respect to other …
Something that needs improvement on DynamoDB in order to become more usable is the possibility to index columns other than the primary key. UPDATE 1 (06/04/2013) On 04/18/2013, Amazon announced support for Local Secondary Indexes, which made DynamoDB f***ing great:
Formatting DynamoDB data to normal JSON in AWS Lambda
2015年9月22日 · import json from boto3.dynamodb.types import TypeDeserializer def ddb_deserialize(r, type_deserializer ...
How to do basic aggregation with DynamoDB? - Stack Overflow
2017年5月24日 · Use DynamoDB connector for Hive and directly query DynamoDB. Again you can write arbitrary SQL queries, but in this case it will access data in DynamoDB directly. The downside is that it will consume read capacity on every query you do. Maintain aggregated data in a separate table using DynamoDB streams. For example you can have a table UserId ...
DynamoDB: Query all data and sorted by date descending
2017年3月9日 · For a list of reserved words, see Reserved Words in the Amazon DynamoDB Developer Guide. For more information on ExpressionAttributeNames and ExpressionAttributeValues, see Using Placeholders for Attribute Names and Values in the Amazon DynamoDB Developer Guide. Type: String. Required: No. Your Scenario Can be …
How to use “IN” statement in FilterExpression using array
2016年10月27日 · Checked AWS document but did not find any working example. Here is my attempt var params = { TableName: "User", IndexName:"a-b-index", KeyConditionExpression: "
searching on array items on a DynamoDB table - Stack Overflow
@Bluetoba there are a few things here, first off its necessary to realize that a QUERY in DynamoDB is NOT required to do a lot of things, it just speeds up the process when compared to a SCAN of the whole table. So you can for sure do the exact same thing you describe with SQL tables using a SCAN and no changes to your keys.
How to use auto increment for primary key id in dynamodb
2016年5月6日 · This is anti-pattern in DynamoDB which is build to scale across many partitions/shards/servers. DynamoDB does not support auto-increment primary keys due to scaling limitations and cannot be guaranteed across multiple servers. Better option is to assemble primary key from multiple indices. Primary key can be up to 2048 bytes. There are few options:
Concurrent updates in DynamoDB, are there any guarantees?
2019年4月2日 · For scenarios like auctions, parallel tick counts (such as "likes"), DynamoDB offers AtomicCounters. If you update a list, that depends on if you use the DynamoDB's list type (L), or if it is just a property and the client translates the lists into a String (S). So if you read a property, change it, and write, and do that in parallel, the ...
Does DynamoDB support aggregate functions like AVG, MAX, MIN?
2014年10月10日 · To get the full count of items that match, take the LastEvaluatedKey value from the previous request, and use that value as the ExclusiveStartKey in the next request. Repeat this until DynamoDB no longer returns a LastEvaluatedKey." –