# Find listings that disappeared between two scraper runs

**Use case:** 

Returns the items that were in the previous dataset but are missing from the current one, for example sold properties, expired job ads or products taken off a shop. Items are matched by the key fields you choose. Use it to mark listings as sold or closed in your own database.

## Input

```json
{
  "keyFields": [
    "url"
  ],
  "ignoreFields": [
    "scrapedAt"
  ],
  "changeTypes": [
    "removed"
  ],
  "ignoreArrayOrder": false
}
```

## Output

```json
{
  "changeType": {
    "label": "Change type",
    "format": "string"
  },
  "key": {
    "label": "Key",
    "format": "string"
  },
  "keyHash": {
    "label": "Key hash",
    "format": "string"
  },
  "changedFields": {
    "label": "Changed fields",
    "format": "array"
  },
  "previousValues": {
    "label": "Previous values",
    "format": "object"
  },
  "item": {
    "label": "Item",
    "format": "object"
  }
}
```

## How it works

### 1. Sign up on Apify or log in

The Dataset Change Tracker Actor is ready to run with the inputs already set for "Find listings that disappeared between two scraper runs". [Sign up or log in](https://console.apify.com/create-task-from-example/2OyHhorwMbCm7gevt) and you'll land in Apify Console with a copy of this exact task.

### 2. Start the "Find listings that disappeared between two scraper runs" task

The Dataset Change Tracker Actor will start running based on the input automatically. You can also change all the input fields, like key fields, fields to ignore, and more, to match your specific use case.

### 3. Receive the "Find listings that disappeared between two scraper runs" output

Monitor the progress in real time. You will be notified as soon as your dataset is complete and ready for review. Each result includes data such as change type, key, key hash, and more.

### 4. Integrate into your workflow

The final output is delivered in JSON, CSV, or Excel format, ready to be plugged into your workflow. You can also [run the "Find listings that disappeared between two scraper runs" task via API](https://apify.com/quietworkslab/dataset-change-tracker.md).

## FAQ

### What does a removed item row contain?

A row from the removed listings task contains the item as it was in the previous dataset, so you keep its last known price, title and other fields.

### Is an item missing because the scraper failed counted as removed?

Yes, the removed listings task cannot tell why an item is missing. Check that the scraper run succeeded and found a normal number of items before you act on removed rows.

### How much does the removed listings task cost?

The Dataset Change Tracker charges $0.00002 per item of the current dataset ($0.02 per 1,000 items), plus Apify's Actor start event.

## About this Actor

This example demonstrates how to use [Dataset Change Tracker](https://apify.com/quietworkslab/dataset-change-tracker.md) with a specific input configuration. Visit the [Actor detail page](https://apify.com/quietworkslab/dataset-change-tracker.md) to learn more, explore other use cases, and run it yourself.


## How to integrate an Actor?

This Task's input is already configured above. Use it as-is rather than inventing a new one.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For full API examples (JavaScript, Python, CLI, MCP, OpenAPI), see this Task's Actor page: https://apify.com/quietworkslab/dataset-change-tracker.md

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).