Seven NoSQL Databases in a Week

Secondary indexes

DynamoDB allows you to create an index on an attribute other than the primary key attribute, known as a secondary index. We can use these indexes in scan and query operations to retrieve data more efficiently.

If an item is inserted, deleted, or updated in the table, DynamoDB will automatically maintain any related secondary index for that table.

DynamoDB supports two types of secondary index:

• Global secondary index: The global secondary index is called global because any attribute in the base table can be used as a partition key in the index. For the global secondary index, you must define one partition key attribute. Here, the sort key attribute is optional, so this can have a simple key as well as a composite key. A ...