-> if error in indexing after upgrade then run below sql query in phpmyadmin
CREATE
SQL SECURITY INVOKER
VIEW `inventory_stock_1`
AS
SELECT
DISTINCT
legacy_stock_status.product_id,
legacy_stock_status.website_id,
legacy_stock_status.stock_id,
legacy_stock_status.qty quantity,
legacy_stock_status.stock_status is_salable,
product.sku
FROM `cataloginventory_stock_status` `legacy_stock_status`
INNER JOIN `catalog_product_entity` product
ON legacy_stock_status.product_id = product.entity_id;
and run below commands
- Clear
var/generation - Clear
var/cache - Enable Magento modules:
bin/magento module:enable --all - Compile DI
bin/magento setup:di:compile
hope this helps you:)