[5.2] Speed up chunk for large sets of data

src/Illuminate/Database/Eloquent/Builder.php

@@ -354,6 +354,37 @@ public function chunk($count, callable $callback)
         return true;
     }
 
+    /**
+     * Chunk the results of a query, when the ID to query by is known.
+     *
+     * Because if we know the ID to key by, then we can get through each page much faster,
+     * especially in larger sets of data.
+     *
+     * @param $count
+     * @param callable $callback
+     * @param $idField
+     * @return bool
+     */
+    public function chunkById($count, callable $callback, $idField)
+    {
+        $lastId = null;
+        $results = $this->pageAfterId($count, $idField)->get();
+
+        while (! $results->isEmpty()) {
+            if (call_user_func($callback, $results) === false) {
+                return false;
+            }
+
+            if ($idField) {
+                $lastId = last($results->all())->{$idField};
+            }
+
+            $results = $this->pageAfterId($count, $idField, $lastId)->get();
+        }
+
+        return true;
+    }
+
     /**
      * Execute a callback over each item while chunking.
      *

src/Illuminate/Database/Query/Builder.php

@@ -1314,6 +1314,23 @@ public function forPage($page, $perPage = 15)
         return $this->skip(($page - 1) * $perPage)->take($perPage);
     }
 
+    /**
+     * Set the limit and query for the next set of results, given the
+     * last scene ID in a set.
+     *
+     * @param int $perPage
+     * @param $idField
+     * @param int $lastId
+     * @return Builder|static
+     */
+    public function pageAfterId($perPage = 15, $idField = 'id', $lastId = 0)
+    {
+        return $this->select($idField)
+            ->where($idField, '>', $lastId)
+            ->orderBy($idField, 'asc')
+            ->take($perPage);
+    }
+
     /**
      * Add a union statement to the query.
      *
@@ -1611,6 +1628,37 @@ public function chunk($count, callable $callback)
         return true;
     }
 
+    /**
+     * Chunk the results of a query, when the ID to query by is known.
+     *
+     * Because if we know the ID to key by, then we can get through each page much faster,
+     * especially in larger sets of data.
+     *
+     * @param $count
+     * @param callable $callback
+     * @param $idField
+     * @return bool
+     */
+    public function chunkById($count, callable $callback, $idField)
+    {
+        $lastId = null;
+        $results = $this->pageAfterId($count, $idField)->get();
+
+        while (! $results->isEmpty()) {
+            if (call_user_func($callback, $results) === false) {
+                return false;
+            }
+
+            if ($idField) {
+                $lastId = last($results->all())->{$idField};
+            }
+
+            $results = $this->pageAfterId($count, $idField, $lastId)->get();
+        }
+
+        return true;
+    }
+
     /**
      * Execute a callback over each item while chunking.
      *

tests/Database/DatabaseEloquentBuilderTest.php

@@ -194,6 +194,22 @@ public function testChunkCanBeStoppedByReturningFalse()
         });
     }
 
+    public function testChunkPaginatesUsingWhereBetweenIds()
+    {
+        $builder = m::mock('Illuminate\Database\Eloquent\Builder[pageAfterId,get]', [$this->getMockQueryBuilder()]);
+        $builder->shouldReceive('pageAfterId')->once()->with(2, 'someIdField')->andReturn($builder);
+        $builder->shouldReceive('pageAfterId')->once()->with(2, 'someIdField', 2)->andReturn($builder);
+        $builder->shouldReceive('pageAfterId')->once()->with(2, 'someIdField', 10)->andReturn($builder);
+
+        $builder->shouldReceive('get')->times(3)->andReturn(
+            new Collection([(object) ['someIdField' => 1], (object) ['someIdField' => 2]]),
+            new Collection([(object) ['someIdField' => 10]]),
+            new Collection([])
+        );
+
+        $builder->chunkById(2, function ($results) {}, 'someIdField');
+    }
+
     public function testPluckReturnsTheMutatedAttributesOfAModel()
     {
         $builder = $this->getBuilder();