How to use “IN” statement in FilterExpression using array - dynamodb

Question

Checked AWS document but did not find any working example.

Here is my attempt

var params = {
            TableName: \"User\",
            IndexName:\         


        

Answer 1

Please refer this answer

Summary:-

For fixed number of values in "IN" clause:-

var params = {
    TableName : "Users",
    FilterExpression : "username IN (:user1, :user2)",
    ExpressionAttributeValues : {
        ":user1" : "john",
        ":user2" : "mike"
    }
};

For more elements in array and forming the FilterExpression dynamically:-

var titleValues = ["The Big New Movie 2012", "The Big New Movie"];
var titleObject = {};
var index = 0;
titleValues.forEach(function(value) {
    index++;
    var titleKey = ":titlevalue"+index;
    titleObject[titleKey.toString()] = value;
});

var params = {
    TableName : "Movies",
    FilterExpression : "title IN ("+Object.keys(titleObject).toString()+ ")",
    ExpressionAttributeValues : titleObject
};

Answer 2

Using es5 and map:

const params = {
  TableName: 'personalizations',
  KeyConditionExpression: 'accountId = :accountId',
  FilterExpression: `websiteId IN (${websites.map(w => `:${w.websiteId}`).join(',')})`,
  ExpressionAttributeValues: {':accountId': accountId}
}
for (const website of websites) {
  params.ExpressionAttributeValues[`:${website.websiteId}`] = website.websiteId
}

const {Items: personalizations} = await docClient.query(params).promise()

Answer 3

notionquest's answer is correct but i cant use my other values in ExpressionAttributeValues like :country and :status so here is modified answer to make it working as per my requirements

var AttributeValuesObject = {};

  AttributeValuesObject[':country '] = "USA";
  AttributeValuesObject[':status'] = 1;

  var titleValues = ["1", "2"];
  var titleObject = {}; 

  var index = 0; 

  titleValues.forEach(function(value) {
    index++;
    var titleKey = ":titleValue"+index;
    AttributeValuesObject[titleKey.toString()] = value;
    titleObject[titleKey.toString()] = value;
  });

  var params = {
    TableName: "User",
    IndexName:"a-b-index",
    KeyConditionExpression: "Country = :country and #s = :status",
    FilterExpression: "Id IN ("+Object.keys(titleObject).toString()+ ")",
    ExpressionAttributeValues: AttributeValuesObject,
    ExpressionAttributeNames: {"#s": "Status"}
  };

  //get users
  dynamodb.query(params, function (err, data) {
    if (err)
      //error
    else {
      //success

    }
   });

Answer 4

The Python3 version:

def get_filter_for_in_clause(column_name, in_values, column_type="S"):
    expressions = []
    for i in range(len(in_values)):
        expressions.append(f':temp{i}')
    filter_expression = f'{column_name} IN ({", ".join(expressions)})'

    expression_attribute_values = {}
    for index, expression in enumerate(expressions):
        expression_attribute_values[expression] = {column_type: in_values[index]}

    return filter_expression, expression_attribute_values

Usage:

column = 'testcolumn'
inputs = ['testvalue1', 'testvalue2', 'testvalue3']
filter_expression, expression_attribute_values = get_filter_for_in_clause(column, inputs)

Result:

# filter_expression = 'testcolumn IN (:temp0, :temp1, :temp2)'
# expression_attribute_values = {':temp0': {'S': 'testvalue1'}, ':temp1': {'S': 'testvalue2'}, ':temp2': {'S': 'testvalue3'}}

Answer 5

You could also use notionquest's approach and simply insert your other attribute values inside the titleObject{}. e.g.

var titleObject = { ": country": "USA", ":status": 1, }; 

Note: You might have to add schema like "S" if you're not using DocumentClient

     var titleObject = { 
      ":country": { "S":"USA" }, ...

}

Answer 6

I've done it like this, parsing the params list once

const users = [{userId:1, name:'joe'}, {userId:2, name:'mike'}]
const expressionAttributeValues = {};
const userIdParams = users.map((u, i) => {
  const userParam = `:user${i}`;
  expressionAttributeValues[userParam] = u.userId;
  return userParam;
}).join(',')
var params = {
    TableName : 'Users',
    FilterExpression : `username IN (${userIdParams})`,
    ExpressionAttributeValues : expressionAttributeValues
};