PropertyDefinition inconsistent

Question

I have following template that i am using in cloudformation UI to create dynamoDB table. I want to create a table with PrimaryKey as ID and sortKey as Value

{
  "AWSTemplateFormatVersion" : "2010-09-09",

  "Description" : "DB Description",

  "Resources" : {
    "TableName" : {
      "Type" : "AWS::DynamoDB::Table",
      "Properties" : {
        "AttributeDefinitions": [ { 
          "AttributeName" : "ID",
          "AttributeType" : "S"
        }, { 
          "AttributeName" : "Value",
          "AttributeType" : "S"
        } ],
        "KeySchema": [
          { 
            "AttributeName": "ID", 
            "KeyType": "HASH"
          }
        ]                
      },
      "TableName": "TableName"
    }
  }
}

On the CF UI, I click on new stack, point to the template file from my local computer, give stack a name and click next. After sometime, I get error that says Property AttributeDefinitions is inconsistent with the KeySchema of the table and the secondary indexes

Solution 1

The issue is that the Resources.Properties.AttributeDefinitions key must only define columns used for indexes or keys. In other words, the keys in Resources.Properties.AttributeDefinitions must match the same keys defined in Resources.Properties.KeySchema.

AWS docs:

AttributeDefinitions: A list of AttributeName and AttributeType objects that describe the key schema for the table and indexes.

so the resulting template would look like this:

{
  "AWSTemplateFormatVersion" : "2010-09-09",

  "Description" : "DB Description",

  "Resources" : {
    "TableName" : {
    "Type" : "AWS::DynamoDB::Table",
    "Properties" : {
      "AttributeDefinitions": [ { 
        "AttributeName" : "ID",
        "AttributeType" : "S"
      } ],
      "ProvisionedThroughput":{
        "ReadCapacityUnits" : 1,
        "WriteCapacityUnits" : 1
      },
      "KeySchema": [
        { 
          "AttributeName": "ID", 
          "KeyType": "HASH"
        }
       ] ,               
      "TableName": "table5"
    }
   }
  }
}

Solution 2

The accepted answer is correct in the cause of the error, but you said you wanted the sort key to be Value. So you should change your CloudFormation to include that:

{
  "AWSTemplateFormatVersion" : "2010-09-09",

  "Description" : "DB Description",

  "Resources" : {
    "TableName" : {
      "Type" : "AWS::DynamoDB::Table",
      "Properties" : {
        "AttributeDefinitions": [ { 
          "AttributeName" : "ID",
          "AttributeType" : "S"
        }, { 
          "AttributeName" : "Value",
          "AttributeType" : "S"
        } ],
        "KeySchema": [
          { 
            "AttributeName": "ID", 
            "KeyType": "HASH"
          },
          { 
            "AttributeName": "Value", 
            "KeyType": "RANGE"
          }
        ]                
      },
      "TableName": "TableName"
    }
  }
}

Comments

[Dilantha]

If we remove the 'value' attribute from AttributeDefinitions how can we add the 'Value' column to the table ?

[ThomasP1988]

stackoverflow.com/questions/25606135/… After a research, there is no need to define all your columns when you create the table, only indexes, then you can add attributes "on the go" when inserting a new row

[ThomasP1988]

stackoverflow.com/questions/47385177/… another answer which explains that

[Jason Wadsworth]

The question stated that Value should be the sort key, so it should be included in the KeySchema, not removed from the AttributeDefinitions.