Naming Rules and Data Types

Naming rules

  • Tables, properties, and other objects in DynamoDB must have names.
  • Following are the naming rules for DynamoDB:
    • All names must be encoded with UTF-8 and have case sensitive.
    • Table name and index name must be from 3 to 255 characters and can only contain the following characters:
      • a-z
      • A-Z
      • 0-9
      • _(underlined)
        • (dash line)
      • . (dots)
  • The attribute name must be at least one character long, but no longer than 64 KB.
  • The following are exceptions. These property names cannot be longer than 255 characters:
    • The key name of the Secondary Index partition.
    • Secondary Index sorts the key names.
    • The name of any user-specified expected properties (applies only to local SecondaryIndexes).

Datatypes

DynamoDB supports many different data types for the attributes in the table. They can be classified as follows:

  • Scalar types: A scalar type can represent exactly one value. Scalar types are numeric, string, binary, Boolean, and null.
  • Document Type: A document type can represent a complex structure with nested properties, such as you will find in a JSON document. The document types are list and map.
  • Set type: A set type can represent many scalar values. Set types are string set, numeric set, and binary set.