How does data regeneration and updating work in Mergado?#

Why it is important to regenerate data#

When you modify rules, filters, or queries in Mergado, or when the input data from your online store changes, it is important for these changes to actually make it into the output feed that you send to advertising channels. Data regeneration is the mechanism that ensures changes from the data source reach Mergado Editor and that edits in the editor are reflected in the output data flowing to the target platforms. Thanks to this mechanism, you gain control over what actually appears in your advertising.

What types of data updates take place in Mergado#

1. Applying rules#

After you make changes in a project (manual edits to selected products, creation of new rules, modification of existing rules), you need to confirm these changes by clicking the Apply rules button. At that moment, the changes based on your edits are performed only within Mergado, and you can review them on the Products page.

When applying rules, no new data is loaded from the input feed, and the rule changes are not reflected in the output feed. Changes are propagated to the output feed (and thus sent to the target advertising platforms) only during data regeneration (whether automatic or manual).

When to use: If you want to verify the impact of a rule on products and check that the rule is set up correctly, without changing the output data and having the changes appear on the target platform (e.g. on Heureka or Google).
How to trigger: In the specific project, on the Rules page, click the Run processes manually button and then select Apply rules.

2. Applying rules only to watched products#

A somewhat faster and more specific way to verify changes that a new or modified rule makes is applying rules only to watched products. In this mode, Mergado again applies rules only within Mergado (without loading new input data and without exporting data to the output feed), but this time only to selected products where you want to monitor changes.

When to use: If you are working on a specific change (e.g. only for a certain category) and want to see the effect quickly without waiting for the entire feed. It is an ideal diagnostic tool for understanding how individual rules change element values for individual products. This option is also ideal when your feed contains thousands of products but the rules only affect some of them, and bulk application to all items in the feed would take unnecessarily long. Applying rules to watched products will save you a lot of time.
How to trigger: In the specific project, first select the products you want to watch. On the Products page, for the selected product, click the Rule walkthrough tab. Here, check the Watch product during rule walkthrough checkbox. Repeat this for all products you want to watch.

On the Rule walkthrough tab, you can also directly trigger the application of rules to watched products by clicking Run rule application. On the Rule walkthrough page, you will then see a list of all rules that modify data for the given product, including the original and resulting state. By checking the Highlight differences checkbox, specific changes will be color-highlighted.

You can also trigger the application of rules to watched products on the Rules page. Here, click the Run processes manually button and then select Apply only to watched.

Similarly, you can start the process on the Settings page, in the Regeneration tab, where in the Apply rules only to watched items section, click the Apply only to watched button.

After the rule application to watched products is completed, a list of all watched products is displayed at the bottom of the page. You can click on individual items, which will take you to the Watched products page where you can immediately review the changes that took place.

3. Regenerating changed items#

When you decide to push the changes through to the advertising platform, you need to synchronize the data. This means Mergado loads new data from the input feed, then applies rules only to products that changed since the last regeneration, and sends this updated data to the output feed (and thus to the target platform).

When to use: If you want the changes to go “live” and be reflected in the output feed as quickly as possible. At the same time, you may not want to fully regenerate the entire feed because of just a few minor changes. You will appreciate this especially if your feed contains thousands of products, where a complete regeneration could take a longer time. This regeneration method is the fastest and most efficient.
How to trigger: In the specific project, on the Rules page, click Run processes manually and then select Regenerate changed.

You can also trigger this process on the Settings page. Here, click the Regeneration tab and in the Regenerate project section, click the Regenerate changed button.

4. Regenerating everything#

This is the same process as in the previous point, but in this case the synchronization is performed on all data. Mergado again loads new data from the input feed, then applies rules, and sends the updated data to the output feed.

During this process, Mergado processes and updates all items completely, including those whose output values do not change after processing. This regeneration method naturally takes significantly longer, especially if you have a large feed.

When to use: If you want to update products that have not changed since the last regeneration as well. You might want this, for example, when errors occurred during the last regeneration, some data was not updated, or other non-standard situations occurred. A complete feed regeneration can help resolve these issues.
How to trigger: In the specific project, go to the Settings page. Click the Regeneration tab and in the Regenerate project section, click the Regenerate all button.

5. Importing input data#

Mergado downloads the latest source data from the input feed and updates the internal data in Mergado. During this process, rules are not applied and the output feed is not affected.

When to use: If changes have occurred in your input data (e.g. you added new products, prices changed) and you want to make edits in Mergado on this new data. At the same time, you do not want the new input feed data to be immediately reflected in the output feed as well.
How to trigger: In the selected project, go to the Settings page. Navigate to the Regeneration tab and in the Regenerate project section, click the Import input data button.

6. Exporting output data#

Mergado exports the current data to the output feed. During this process, current data is not downloaded from the input feed, and rules are not applied. If you want the export to include rules and edits you previously made, you need to first confirm the changes by clicking Apply rules.

When to use: If you want changes you made in Mergado to immediately appear on the advertising platform (e.g. before launching a campaign), but at the same time you do not want to reload the input feed (e.g. due to a limited number of downloads on the online store platform side).
How to trigger: In the selected project, go to the Settings page. Navigate to the Regeneration tab and in the Regenerate project section, click the Run export button.

7. Automatic regeneration by Mergado#

Mergado automatically performs regeneration several times a day to keep your output feed data always up to date. This automatic synchronization follows the same process as regenerating changed items. Only what has changed since the last regeneration is automatically regenerated (not the entire feed).

When does automatic regeneration occur?#

After creating a project, the automatic data regeneration function starts running and does not need to be enabled manually. Regeneration occurs several times a day and primarily depends on changes in the input feed – the more frequently the input feed data changes, the more frequently Mergado regenerates to keep the output feed as current as possible.

How to disable or re-enable automatic regeneration?#

If you are making extensive changes to the feed and do not want to risk automatic regeneration starting during your work – which would push incomplete or untested changes into the output feed – you can easily pause automatic regeneration and re-enable it when the time is right.

In the project where you are making changes, go to the Settings section. Click the Regeneration tab and in the Scheduled regenerations section, click the Pause regeneration button to temporarily stop automatic data synchronization.

Once you have finished the necessary feed adjustments, simply re-enable automatic regeneration in the same place by clicking the Allow regeneration button.

How to schedule automatic data regeneration?#

If you do not want Mergado to schedule regeneration on its own and want full control over the process, you can simply set up regeneration for specific times.

In the selected project, go to the Settings page. Click the Regeneration tab and navigate to the Regeneration settings section.
Click the Edit button. In the Manual section, you can set up to 6 time slots for project regeneration. The minimum interval between individual slots must be at least 2 hours.
Then select the time zone and click Save.

If you want to switch manually configured regeneration back to automatic, go back to the Regeneration settings section, click Edit, then Automatic, and confirm by clicking Save.

How to find out when a project was regenerated?#

You can easily check how often a specific project is being regenerated in the History tab. Here you can monitor individual processes, and in the Event type column, you can select and filter the specific type of regeneration you want to track, e.g. Product import, Rule application, or Product export.

History also distinguishes between scheduled regeneration (within manual or automatic settings), e.g. Scheduled product import, and one-time manually triggered regeneration, e.g. Product import.

FAQ#

What does “regeneration” mean in Mergado?#

Regeneration is a process in which Mergado loads current data from the input feed, applies your rules and edits, and sends the updated data to the output feed. It ensures that your advertising channels (e.g. Heureka, Google, or Facebook) display correctly edited and up-to-date information.

What is the difference between “applying rules” and “regeneration”?#

Applying rules takes place only within Mergado. Mergado modifies data according to your rules, but the changes are not pushed to the output feed.
Regeneration transfers these edits “live” to the output feed, which is downloaded by advertising platforms.

In other words: “Apply rules” is essentially a testing step, “Regenerate” means publishing changes to the output feed.

When should I use “Apply rules”?#

When you want to verify how rules affect products without immediately publishing these changes to the output feed. For example, when testing new conditions or checking whether a rule works correctly.

When should I use “Apply rules only to watched products”?#

Use this feature when you need to test the impact of rules on specific products or categories only, without processing the entire feed. It is an ideal way to quickly find out whether rules work as expected.

What does “Regenerate changed” mean?#

During this process, Mergado:

Loads current input data.
Applies rules.
Updates only products that have changed since the last regeneration and sends the updated data to the output feed.

This is the fastest and most common way to update data, suitable for daily data synchronization, for example.

What does “Regenerate all” mean?#

During this process, Mergado:

Loads current input data.
Applies rules.
Updates all products in the feed, not just those affected by changes.

This regeneration method takes longer but is suitable after extensive rule changes, when you suspect errors occurred in the previous regeneration, or when you need certainty that all data has been reprocessed from scratch.

What is “Import input data” for?#

During this process, the current version of your input feed is downloaded into Mergado, but rules are not applied and data is not exported to the output feed. Use this step when you want to first work with new data in the editor (e.g. test rules) but do not yet want the changes to appear in your advertising.

What is “Export output data” for?#

During this process, current data from Mergado is exported to the output feed, which advertising systems then download. During a standalone export, new input data is not imported and rules are not re-applied. The data is processed as it currently exists in Mergado. Use this step, for example, when you want to manually trigger an output feed update before launching a campaign but do not want to reload the entire input feed.

How often does automatic regeneration occur?#

Automatic regeneration occurs several times a day, depending on the activity in your input feed. If the feed data changes frequently, Mergado regenerates it more often. If you want full control over the timing, you can set it manually and choose up to 6 time slots per day.

Can I schedule regeneration for a specific time?#

Yes. For the selected project, in Settings -> Regeneration -> Regeneration settings, click the Edit button. Choose the Manual option and here you can select up to 6 time slots per day (with a minimum interval of 2 hours). Confirm by clicking Save. This determines when your project will be automatically regenerated.

How do I pause and re-enable automatic regeneration?#

On the Settings page, go to Regeneration. In the Regeneration settings section, click the Pause regeneration button, which will temporarily disable automatic data updates. When you want to resume the process, simply click Allow regeneration in the same place.

You will find this feature useful, for example, during major data modifications when you do not want unfinished changes to be pushed to the output data.

How do I find out when the last regeneration took place?#

For the selected project, go to the Overview page. Here you will see when the last import, rule application, export, and output feed access occurred.

If you want to find out when these processes took place further in the past, go to the History page for the selected project. Here you will find all project events, including the type of process, date, and time of their execution.

Can I work on other projects during regeneration?#

Yes. Regeneration runs in the background on Mergado’s server, so you can switch between projects, tabs, or even close the browser. The process will not be interrupted, and you can later check its status on the History page.

Can regeneration be sped up?#

Partially. Regeneration will be faster, for example, if you choose Regenerate changed, where only products with changes are processed, instead of Regenerate all, where the entire feed is processed. You can also speed things up by setting up rules efficiently – meaning, if possible, use one rule for the desired modification instead of two or more. However, the overall regeneration duration is most affected by the feed size.

Can I regenerate only some products or a specific product?#

Technically yes, but you need to be careful during the process. If you mark certain products as watched, then set up a rule, apply it only to these watched products, and then use the Regenerate changed option, the changes will indeed only affect the watched products. However, during this process you must not make any other changes to other products, because when you trigger Regenerate changed, those additional changes would also be pushed to the output feed.

Can I cancel or stop a regeneration in progress?#

Yes. If you started a regeneration but want to cancel it during the process, simply click the Cancel button. The process will terminate immediately, and if the regeneration did not complete fully, the output feed will not be updated.

How soon after regeneration do changes appear in the output feed?#

Changes appear in the output feed immediately after regeneration is completed. Platforms such as Heureka or Google Merchant Center then fetch data from this feed according to their own schedule.

How do I know that regeneration has completed?#

On the History page for the project, you can see a list of all completed processes, including the date, time, type, and result. Here you can verify that regeneration has indeed taken place.