Merge branch '2.4-develop' into functional--test--automation

Author: manjusha729

app/code/Magento/AdvancedPricingImportExport/Model/Import/AdvancedPricing.php

@@ -390,6 +390,7 @@ protected function saveAndReplaceAdvancedPrices()
         $listSku = [];
         $tierPrices = [];
         while ($bunch = $this->_dataSourceModel->getNextBunch()) {
+            $bunchTierPrices = [];
             foreach ($bunch as $rowNum => $rowData) {
                 if (!$this->validateRow($rowData, $rowNum)) {
                     $this->addRowError(ValidatorInterface::ERROR_SKU_IS_EMPTY, $rowNum);
@@ -403,7 +404,7 @@ protected function saveAndReplaceAdvancedPrices()
                 $rowSku = $rowData[self::COL_SKU];
                 $listSku[] = $rowSku;
                 if (!empty($rowData[self::COL_TIER_PRICE_WEBSITE])) {
-                    $tierPrices[$rowSku][] = [
+                    $tierPrice = [
                         'all_groups' => $rowData[self::COL_TIER_PRICE_CUSTOMER_GROUP] == self::VALUE_ALL_GROUPS,
                         'customer_group_id' => $this->getCustomerGroupId(
                             $rowData[self::COL_TIER_PRICE_CUSTOMER_GROUP]
@@ -415,17 +416,26 @@ protected function saveAndReplaceAdvancedPrices()
                             ? $rowData[self::COL_TIER_PRICE] : null,
                         'website_id' => $this->getWebSiteId($rowData[self::COL_TIER_PRICE_WEBSITE])
                     ];
+                    if (\Magento\ImportExport\Model\Import::BEHAVIOR_APPEND == $behavior) {
+                         $bunchTierPrices[$rowSku][] = $tierPrice;
+                    }
+                    if (\Magento\ImportExport\Model\Import::BEHAVIOR_REPLACE == $behavior) {
+                        $tierPrices[$rowSku][] = $tierPrice;
+                    }
                 }
             }
 
             if (\Magento\ImportExport\Model\Import::BEHAVIOR_APPEND == $behavior) {
-                $this->processCountExistingPrices($tierPrices, self::TABLE_TIER_PRICE)
-                    ->processCountNewPrices($tierPrices);
+                $this->processCountExistingPrices($bunchTierPrices, self::TABLE_TIER_PRICE)
+                    ->processCountNewPrices($bunchTierPrices);
 
-                $this->saveProductPrices($tierPrices, self::TABLE_TIER_PRICE);
-                if ($listSku) {
-                    $this->setUpdatedAt($listSku);
-                }
+                $this->saveProductPrices($bunchTierPrices, self::TABLE_TIER_PRICE);
+            }
+        }
+
+        if (\Magento\ImportExport\Model\Import::BEHAVIOR_APPEND == $behavior) {
+            if ($listSku) {
+                $this->setUpdatedAt($listSku);
             }
         }