From bd24947fd1fc49d37354cd1195b4e5756e5560d4 Mon Sep 17 00:00:00 2001
From: Nathan Ward <nathanward213@gmail.com>
Date: Tue, 27 Nov 2018 21:47:12 +0000
Subject: [PATCH 1/3] Fixes ordering by a relationship.

---
 src/QueryDataTable.php | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/QueryDataTable.php b/src/QueryDataTable.php
index 1ac591df..0b1c7128 100644
--- a/src/QueryDataTable.php
+++ b/src/QueryDataTable.php
@@ -617,6 +617,13 @@ protected function defaultOrdering()
             })
             ->each(function ($orderable) {
                 $column = $this->resolveRelationColumn($orderable['name']);
+                
+                if (str_contains($column, '.')) {
+                    $this->query->addSelect([
+                        $this->query->getModel()->getTable() . '.*',
+                        $column
+                    ]);
+                }
 
                 if ($this->hasOrderColumn($column)) {
                     $this->applyOrderColumn($column, $orderable);

From cf570090ccb30f29e833bc8d2c734171fd104876 Mon Sep 17 00:00:00 2001
From: Nathan Ward <nathanward213@gmail.com>
Date: Tue, 27 Nov 2018 22:35:42 +0000
Subject: [PATCH 2/3] Added a check for duplicate selects.

---
 src/QueryDataTable.php | 28 ++++++++++++++++++++++++----
 1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/src/QueryDataTable.php b/src/QueryDataTable.php
index 0b1c7128..3d5ed941 100644
--- a/src/QueryDataTable.php
+++ b/src/QueryDataTable.php
@@ -619,10 +619,7 @@ protected function defaultOrdering()
                 $column = $this->resolveRelationColumn($orderable['name']);
                 
                 if (str_contains($column, '.')) {
-                    $this->query->addSelect([
-                        $this->query->getModel()->getTable() . '.*',
-                        $column
-                    ]);
+                    $this->applySelects([$column]);
                 }
 
                 if ($this->hasOrderColumn($column)) {
@@ -635,6 +632,29 @@ protected function defaultOrdering()
                 }
             });
     }
+    
+    /**
+     * Apply selects to query.
+     *
+     * @param array $selects
+     */
+    public function applySelects(array $selects)
+    {
+        $selects = array_merge(
+            [$this->query->getModel()->getTable() . '.*'],
+            $selects
+        );
+
+        $columns = $this->query->getQuery()->columns ?? [];
+
+        $this->query->addSelect(
+            collect($selects)
+                ->unique()
+                ->reject(function ($select) use ($columns) {
+                    return in_array($select, $columns);
+                })->toArray()
+        );
+    }
 
     /**
      * Check if column has custom sort handler.

From 9a2ceb7c2409c7de9b1899431ceaf8343dc208de Mon Sep 17 00:00:00 2001
From: Nathan Ward <nathanward213@gmail.com>
Date: Tue, 27 Nov 2018 23:17:36 +0000
Subject: [PATCH 3/3] Fixed styling issues.

---
 src/QueryDataTable.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/QueryDataTable.php b/src/QueryDataTable.php
index 3d5ed941..5a22dc50 100644
--- a/src/QueryDataTable.php
+++ b/src/QueryDataTable.php
@@ -617,7 +617,7 @@ protected function defaultOrdering()
             })
             ->each(function ($orderable) {
                 $column = $this->resolveRelationColumn($orderable['name']);
-                
+
                 if (str_contains($column, '.')) {
                     $this->applySelects([$column]);
                 }
@@ -632,7 +632,7 @@ protected function defaultOrdering()
                 }
             });
     }
-    
+
     /**
      * Apply selects to query.
      *