How to update stock and prices when using third party tool or ERP in Magento?

For Magento 1 & Magento 2 (Klevu module version 2.x < 2.11.0 and 3.x < 3.3.0)

1. Login into the Magento admin panel
2. For  Magento 1 
   Go to System → Configuration → Klevu → Search Configuration
   For  Magento 2 
   Go to Stores → Configuration → Klevu → Search Configuration
3. Go to Developer Settings (the option is visible at “default config” level)
4. Select “are using an ERP OR 3rd party tool for product updates” to “Yes”
5. Click on Save Config button

For Magento 2 (Klevu module version 2.x >= 2.11.0 and 3.x >= 3.3.0)

The above ERP setting has been removed and replaced with an indexer (Klevu Product Sync Indexer) to handle price and stock updates. This indexer uses a change log table to track changes to prices and stock. This table is added by Magento via mview when the Klevu Product Sync Indexer is set to Update By Schedule. If the indexer is set to Update On Save then Magento will not create this table and any changes made via an ERP or as a result of special price or catalog rule dates will not be synced with Klevu.

This ensures not only ERP changes to prices and stock are synced to Klevu but also price changes triggered by special price and/or catalog rule dates starting or ending.

We also recommend setting the price and stock indexers to Update By Schedule. This is not essential, however, if the price indexer is set to Update On Save, this triggers all prices to be indexed when one price is updated. In turn, this will trigger a full sync to Klevu. This is very inefficient. If the Price indexer is set to Update By Schedule, then only the updated product prices are indexed and therefore only those products are synced to Klevu. This is much more efficient.

To change the indexer mode:

1. Login into the Magento admin panel
2. Go to System > Index Management.
3. Select the checkboxes for Stock, Product Price and Klevu Product Sync Indexer.
4. From the Mass actions dropdown select Update By Schedule.

Klevu Product Sync Indexer should already be set to UPDATE BY SCHEDULE during creation.

Core Magento Bug for Catalog Rule Prices

There is a core Magento bug (prior to Magento 2.4.5) that removes core Magento triggers from the Catalog Rule Price table when a full index runs. This will stop catalog rule prices from being updated correctly. This in turn would stop these products from syncing to Klevu. Magento has released a patch for this bug which can be found here: MDVA-43601: Triggers are removed from.