Automatic Distribution: The default option, Redshift automatically manages your distribution strategy for you, shifting from an initial ALL strategy (for smaller tables) to EVEN distribution (for larger tables). Note: Redshift will not automatically switch back from EVEN to ALL.
Even Distribution: With the EVEN distribution, the leader node distributes rows equally across all slices. This is appropriate for tables that do not participate in joining.
Key Distribution: With the KEY distribution, rows are distributed according to a selected column. Tables that share common join keys are physically co-located for performance.
All Distribution: A copy of the entire data set is stored on each node. This slows down inserting, updating, and querying. This distribution method is only appropriate for small or rarely-updated data sets.
You need to know the DynamoDB partition sizing formula by heart: (Desired RCU/3000 RCU) + (Desired WCU/1000 RCU) = # of partitions needed
AWS Machine Learning does not support unsupervised learning - you will need Apache Spark or Spark MLLib for real-time anomaly detection.
In the context of evaluating a Redshift query plan, DS_DIST_NONE and DS_DIST_ALL_NONE are good. They indicate that no distribution was required for that step because all of the joins are co-located.
DS_DIST_INNER means that the step will probably have a relatively high cost because the inner table is being redistributed to the nodes. DS_DIST_ALL_INNER, DS_BCAST_INNER and DS_DIST_BOTH are not good. (Source)
You must disable cross-region snapshots for Redshift before changing the encryption type of the cluster.
Amazon recommends allocating three dedicated master nodes for each production ElasticSearch domain.
To make your data searchable in CloudSearch, you need to format it in JSON or XML.
You can use popular BI tools like Excel, MicroStrategy, QlikView, and Tableau with EMR to explore and visualize your data. Many of these tools require an ODBC (Open Database Connectivity) or JDBC (Java Database Connectivity) driver. (Source)
Mahout is a machine learning library with tools for clustering, classification, and several types of recommenders, including tools to calculate most-similar items or build item recommendations for users. Use it to carry out Machine Learning work on top of Hadoop.
When preparing to use a Lambda/Kinesis combination, make sure to optimize your Lambda memory and batch size, and adjust the number of shards used by the Kinesis streams.
Triggers do not exist in Redshift.
Amazon Kinesis Aggregators is a Java framework that enables the automatic creation of real-time aggregated time series data from Kinesis streams. (Source)
You can’t encrypt an existing DynamoDB table. You need to create a new, encrypted table and transfer your data over. (Source)
Presto is a fast SQL query engine designed for interactive analytic queries over large datasets from multiple sources. (Source)