nodejs Dynamo DB document client. How to write filter expression for an attribute that exists with null data type

Question

I have an attribute with null value. and some rows have boolean value. Now I want to write a filter expression to filter for the rows with attribute having null value. I am using dynamodb document client.

Answer 1

If you look at the docs , for a scan you can do:

ScanFilter: {
    '<AttributeName>': {
      ComparisonOperator: EQ | NE | IN | LE | LT | GE | GT | BETWEEN | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH, /* required */
      AttributeValueList: [
        someValue /* "str" | 10 | true | false | null | [1, "a"] | {a: "b"} */,
        /* more items */
      ]
    },
    /* '<AttributeName>': ... */
  }

If you are using query :

QueryFilter: {
    '<AttributeName>': {
      ComparisonOperator: EQ | NE | IN | LE | LT | GE | GT | BETWEEN | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH, /* required */
      AttributeValueList: [
        someValue /* "str" | 10 | true | false | null | [1, "a"] | {a: "b"} */,
        /* more items */
      ]
    },
    /* '<AttributeName>': ... */
  },

They both clearly support filtering by attributes with value null .