var params = {
    TableName: 'users',
    Key: {
        'userId': '123'
    },
    UpdateExpression: 'SET isActive = :isActiveVal',
    ConditionExpression: 'userId = :userIdVal and isActive <> :isActiveVal',
    ExpressionAttributeValues: {
        ':userIdVal': '123',
        ':isActiveVal': 'false'
    },
    ReturnValues: "ALL_NEW"
};