DynamoDB: Value provided in ExpressionAttributeNames unused in expressions: keys: {#date}

Question

I am trying to update an item by changing value of isRelevant to true:

       var params = {
              TableName: "test",
              Key: {
                  "#date": data.Items[i].date.N,
                  "accountid": data.Items[i].accountid.S
              },
              UpdateExpression: "set #uu = :x",
              ExpressionAttributeValues: {
                  ":x": {"BOOL": false}
              },
              ExpressionAttributeNames: {
                   '#uu': "isRelevant",
                   '#date': "date"
              }
          };
          
          docClient.update(params, function(err, data) {
              if (err) console.log(err);
              else {
                  console.log('worked');
              }
          });

What is wrong in this code? I tried all possible ways, but still not working!

Answer 1

You don't need to use attribute name mapping for your keys in dynamo.

At the moment you params read like you have a key called '#date' and that you've randomly declared an attribute called '#date' that you're not using.

Instead try:

var params = {
  TableName: "test",
  Key: { "date": data.Items[i].date, "accountid": data.Items[i].accountid },
  UpdateExpression: "set #uu = :x",
  ExpressionAttributeValues: { ":x": false },
  ExpressionAttributeNames: { '#uu': "isRelevant" }
};

Also- when using DynamoDB.DocumentClient, you should use JSON values and it'll deal with the marshalling info the dynamo typed format.

Answer 2

If your date id not Key in dynamoDB than you have to use in ConditionExpression

Example :

let queryParams = {
      TableName: "test",
      Key: {
        'accountid': data.Items[i].accountid
      },
      UpdateExpression: "set #uu = :x",
      ConditionExpression: 'date = :date',
      ExpressionAttributeValues: {
        ':x': false,
        ':date': data.Items[i].date,
      },
      ExpressionAttributeNames: {
        '#uu': "isRelevant"
   }
};