From fc95a5e129e43c828405064b012e9c5a361b7675 Mon Sep 17 00:00:00 2001
From: Thiago Lima <thiagolimaufrj@gmail.com>
Date: Mon, 30 Apr 2018 13:31:10 +0200
Subject: [PATCH 1/2] #14918 improve Indexer Batch Provider

---
 .../Framework/Indexer/BatchProvider.php       | 29 +++++--------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/lib/internal/Magento/Framework/Indexer/BatchProvider.php b/lib/internal/Magento/Framework/Indexer/BatchProvider.php
index 9f8a1b1ace401..b3326c6bb56ea 100644
--- a/lib/internal/Magento/Framework/Indexer/BatchProvider.php
+++ b/lib/internal/Magento/Framework/Indexer/BatchProvider.php
@@ -5,7 +5,8 @@
  */
 namespace Magento\Framework\Indexer;
 
-use \Magento\Framework\DB\Adapter\AdapterInterface;
+use Magento\Framework\DB\Adapter\AdapterInterface;
+use Magento\Framework\DB\Select;
 
 /**
  * Generator of consecutive entity ID ranges that must be handled as a batch.
@@ -24,22 +25,15 @@ public function getBatches(AdapterInterface $adapter, $tableName, $linkField, $b
             $adapter->select()->from(
                 ['entity' => $tableName],
                 [
-                    'max_value' => new \Zend_Db_Expr('MAX(entity.' . $linkField . ')')
+                    'max_value' => new \Zend_Db_Expr('COUNT(*)')
                 ]
             )
         );
 
-        /** @var int $truncatedBatchSize size of the last batch that is smaller than expected batch size */
-        $truncatedBatchSize = $maxLinkFieldValue % $batchSize;
-        /** @var int $fullBatchCount count of the batches that have expected batch size */
-        $fullBatchCount = ($maxLinkFieldValue - $truncatedBatchSize) / $batchSize;
+        $fullBatchCount = ceil($maxLinkFieldValue / $batchSize);
 
         for ($batchIndex = 0; $batchIndex < $fullBatchCount; $batchIndex ++) {
-            yield ['from' => $batchIndex * $batchSize + 1, 'to' => ($batchIndex + 1) * $batchSize];
-        }
-        // return the last batch if it has smaller size
-        if ($truncatedBatchSize > 0) {
-            yield ['from' => $fullBatchCount * $batchSize + 1, 'to' => $maxLinkFieldValue];
+            yield ['limit' => $batchSize, 'offset' => $batchIndex * $batchSize];
         }
     }
 
@@ -47,18 +41,11 @@ public function getBatches(AdapterInterface $adapter, $tableName, $linkField, $b
      * @inheritdoc
      */
     public function getBatchIds(
-        \Magento\Framework\DB\Adapter\AdapterInterface $connection,
-        \Magento\Framework\DB\Select $select,
+        AdapterInterface $connection,
+        Select $select,
         array $batch
     ) {
-        $betweenCondition = sprintf(
-            '(%s BETWEEN %s AND %s)',
-            'entity_id',
-            $connection->quote($batch['from']),
-            $connection->quote($batch['to'])
-        );
-
-        $ids = $connection->fetchCol($select->where($betweenCondition));
+        $ids = $connection->fetchCol($select->order('entity_id')->limit($batch['limit'], $batch['offset']));
         return array_map('intval', $ids);
     }
 }

From 29fab6ee3ca13135eb7737b67caaa51a8c892911 Mon Sep 17 00:00:00 2001
From: Thiago Lima <thiagolimaufrj@gmail.com>
Date: Tue, 1 May 2018 13:21:10 +0200
Subject: [PATCH 2/2] #14918 refactor unit test

---
 .../Indexer/Test/Unit/BatchProviderTest.php   | 46 ++++++++++++++++---
 1 file changed, 39 insertions(+), 7 deletions(-)

diff --git a/lib/internal/Magento/Framework/Indexer/Test/Unit/BatchProviderTest.php b/lib/internal/Magento/Framework/Indexer/Test/Unit/BatchProviderTest.php
index 06d9f58c2f2ec..f22eaaa59ed71 100644
--- a/lib/internal/Magento/Framework/Indexer/Test/Unit/BatchProviderTest.php
+++ b/lib/internal/Magento/Framework/Indexer/Test/Unit/BatchProviderTest.php
@@ -51,10 +51,42 @@ public function testGetBatches($batchSize, $maxLinkFieldValue, $expectedResult)
     public function getBatchesDataProvider()
     {
         return [
-            [200, 600, [['from' => 1, 'to' => 200], ['from' => 201, 'to' => 400], ['from' => 401, 'to' => 600]]],
-            [200, 555, [['from' => 1, 'to' => 200], ['from' => 201, 'to' => 400], ['from' => 401, 'to' => 555]]],
-            [200, 10, [['from' => 1, 'to' => 10]]],
-            [200, 0, []],
+            [
+                100,
+                200,
+                [
+                    ['limit' => 100, 'offset' => 0],
+                    ['limit' => 100, 'offset' => 100]
+                ]
+
+            ],
+            [
+                30,
+                66,
+                [
+                    ['limit' => 30, 'offset' => 0],
+                    ['limit' => 30, 'offset' => 30],
+                    ['limit' => 30, 'offset' => 60]
+                ]
+            ],
+            [
+                200,
+                50,
+                [
+                    ['limit' => 200, 'offset' => 0],
+                    ['limit' => 200, 'offset' => 50],
+                    ['limit' => 200, 'offset' => 100],
+                    ['limit' => 200, 'offset' => 150],
+                    ['limit' => 200, 'offset' => 200]
+                ]
+            ],
+            [
+                100,
+                100,
+                [
+                    ['limit' => 100, 'offset' => 0]
+                ]
+            ]
         ];
     }
 
@@ -63,12 +95,12 @@ public function testGetBatchIds()
         $selectMock = $this->createMock(Select::class);
         $adapterMock = $this->createMock(AdapterInterface::class);
 
-        $selectMock->expects($this->once())->method('where')->with('(entity_id BETWEEN 10 AND 100)')->willReturnSelf();
-        $adapterMock->expects($this->atLeastOnce())->method('quote')->willReturnArgument(0);
+        $selectMock->expects($this->once())->method('order')->with('entity_id')->willReturnSelf();
+        $selectMock->expects($this->once())->method('limit')->with(100, 0)->willReturnSelf();
         $adapterMock->expects($this->once())->method('fetchCol')->with($selectMock, [])->willReturn([1, 2, 3]);
         $this->assertEquals(
             [1, 2, 3],
-            $this->model->getBatchIds($adapterMock, $selectMock, ['from' => 10, 'to' => 100])
+            $this->model->getBatchIds($adapterMock, $selectMock, ['limit' => 100, 'offset' => 0])
         );
     }
 }