Dynamo DB Attribute type boolean

问题

Why can an attribute definition only be of types `{string, number, binary).

See Java SDK class com.amazonaws.services.dynamodbv2.model.AttributeDefinition or documentation.

What if I am trying to define a boolean attribute of type BOOL as mentioned here or here as a distinct type from a number (perhaps this is already the problem, maybe I shouldn't be trying to do this?)

I'm not clear why I cannot define the attribute type explicitly as BOOL. Is this because it's actually just a number 0/1? I would have assumed the above, had it not been for other documentation which talks about booleans as distinct type and annotations in the Java SDK like com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBConvertedBool or @DynamoDBTyped(DynamoDBMapperFieldModel.DynamoDBAttributeType.BOOL) which again seems to indicate that there is some type of distinct definition that can be used.

amazon-dynamodb

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回答1:

This only is the case for key attributes

Each primary key attribute must be a scalar (meaning that it can hold only a single value). The only data types allowed for primary key attributes are string, number, or binary. There are no such restrictions for other, non-key attributes.

https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.CoreComponents.html#HowItWorks.CoreComponents.PrimaryKey

来源：https://stackoverflow.com/questions/51930418/dynamo-db-attribute-type-boolean