diff --git a/framework/core/migrations/2018_01_11_094000_change_access_tokens_add_foreign_keys.php b/framework/core/migrations/2018_01_11_094000_change_access_tokens_add_foreign_keys.php
index b6125506d..3103a963e 100644
--- a/framework/core/migrations/2018_01_11_094000_change_access_tokens_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_11_094000_change_access_tokens_add_foreign_keys.php
@@ -19,7 +19,7 @@ return [
         $schema->getConnection()
             ->table('access_tokens')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_11_155300_change_discussions_add_foreign_keys.php b/framework/core/migrations/2018_01_11_155300_change_discussions_add_foreign_keys.php
index 3e33b765c..23d6b338c 100644
--- a/framework/core/migrations/2018_01_11_155300_change_discussions_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_11_155300_change_discussions_add_foreign_keys.php
@@ -21,7 +21,7 @@ return [
 
         $selectId = function ($table, $column) use ($connection) {
             return new Expression(
-                '('.$connection->table($table)->whereRaw("id = $column")->select('id')->toSql().')'
+                '('.$connection->table($table)->whereColumn('id', $column)->select('id')->toSql().')'
             );
         };
 
diff --git a/framework/core/migrations/2018_01_15_071900_change_discussion_user_add_foreign_keys.php b/framework/core/migrations/2018_01_15_071900_change_discussion_user_add_foreign_keys.php
index 4a9d69a07..c3bf1d9fd 100644
--- a/framework/core/migrations/2018_01_15_071900_change_discussion_user_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_15_071900_change_discussion_user_add_foreign_keys.php
@@ -19,10 +19,10 @@ return [
         $connection = $schema->getConnection();
         $connection->table('discussion_user')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->orWhereNotExists(function ($query) {
-                $query->selectRaw(1)->from('discussions')->whereRaw('id = discussion_id');
+                $query->selectRaw(1)->from('discussions')->whereColumn('id', 'discussion_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_15_072700_change_email_tokens_add_foreign_keys.php b/framework/core/migrations/2018_01_15_072700_change_email_tokens_add_foreign_keys.php
index c840045e6..243b706f3 100644
--- a/framework/core/migrations/2018_01_15_072700_change_email_tokens_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_15_072700_change_email_tokens_add_foreign_keys.php
@@ -19,7 +19,7 @@ return [
         $schema->getConnection()
             ->table('email_tokens')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_18_130500_change_group_permission_add_foreign_keys.php b/framework/core/migrations/2018_01_18_130500_change_group_permission_add_foreign_keys.php
index f783547a6..267a09dc0 100644
--- a/framework/core/migrations/2018_01_18_130500_change_group_permission_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_18_130500_change_group_permission_add_foreign_keys.php
@@ -19,7 +19,7 @@ return [
         $schema->getConnection()
             ->table('group_permission')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('groups')->whereRaw('id = group_id');
+                $query->selectRaw(1)->from('groups')->whereColumn('id', 'group_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_18_130700_change_group_user_add_foreign_keys.php b/framework/core/migrations/2018_01_18_130700_change_group_user_add_foreign_keys.php
index 028b35e94..79a5ef2a5 100644
--- a/framework/core/migrations/2018_01_18_130700_change_group_user_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_18_130700_change_group_user_add_foreign_keys.php
@@ -19,10 +19,10 @@ return [
         $schema->getConnection()
             ->table('group_user')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->orWhereNotExists(function ($query) {
-                $query->selectRaw(1)->from('groups')->whereRaw('id = group_id');
+                $query->selectRaw(1)->from('groups')->whereColumn('id', 'group_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_18_133100_change_notifications_add_foreign_keys.php b/framework/core/migrations/2018_01_18_133100_change_notifications_add_foreign_keys.php
index 442ae1dbd..4845222cb 100644
--- a/framework/core/migrations/2018_01_18_133100_change_notifications_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_18_133100_change_notifications_add_foreign_keys.php
@@ -19,14 +19,14 @@ return [
         $schema->getConnection()
             ->table('notifications')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->delete();
 
         $schema->getConnection()
             ->table('notifications')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = from_user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'from_user_id');
             })
             ->update(['from_user_id' => null]);
 
diff --git a/framework/core/migrations/2018_01_18_134500_change_password_tokens_add_foreign_keys.php b/framework/core/migrations/2018_01_18_134500_change_password_tokens_add_foreign_keys.php
index 7e3c3c6d4..cb7303e71 100644
--- a/framework/core/migrations/2018_01_18_134500_change_password_tokens_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_18_134500_change_password_tokens_add_foreign_keys.php
@@ -19,7 +19,7 @@ return [
         $connection = $schema->getConnection();
         $connection->table('password_tokens')
             ->whereNotExists(function ($query) {
-                $query->selectRaw(1)->from('users')->whereRaw('id = user_id');
+                $query->selectRaw(1)->from('users')->whereColumn('id', 'user_id');
             })
             ->delete();
 
diff --git a/framework/core/migrations/2018_01_18_135100_change_posts_add_foreign_keys.php b/framework/core/migrations/2018_01_18_135100_change_posts_add_foreign_keys.php
index 2a0623052..3ac447273 100644
--- a/framework/core/migrations/2018_01_18_135100_change_posts_add_foreign_keys.php
+++ b/framework/core/migrations/2018_01_18_135100_change_posts_add_foreign_keys.php
@@ -21,7 +21,7 @@ return [
 
         $selectId = function ($table, $column) use ($connection) {
             return new Expression(
-                '('.$connection->table($table)->whereRaw("id = $column")->select('id')->toSql().')'
+                '('.$connection->table($table)->whereColumn('id', $column)->select('id')->toSql().')'
             );
         };
 
diff --git a/framework/core/src/Discussion/DiscussionRepository.php b/framework/core/src/Discussion/DiscussionRepository.php
index de0b7ee36..588132d7b 100644
--- a/framework/core/src/Discussion/DiscussionRepository.php
+++ b/framework/core/src/Discussion/DiscussionRepository.php
@@ -51,7 +51,7 @@ class DiscussionRepository
     {
         return Discussion::leftJoin('discussions_users', 'discussions_users.discussion_id', '=', 'discussions.id')
             ->where('user_id', $user->id)
-            ->whereRaw('last_read_post_number >= last_post_number')
+            ->whereColumn('last_read_post_number', '>=', 'last_post_number')
             ->pluck('id')
             ->all();
     }
diff --git a/framework/core/src/Discussion/Search/Gambit/FulltextGambit.php b/framework/core/src/Discussion/Search/Gambit/FulltextGambit.php
index 81f5e5976..d925e0ec8 100644
--- a/framework/core/src/Discussion/Search/Gambit/FulltextGambit.php
+++ b/framework/core/src/Discussion/Search/Gambit/FulltextGambit.php
@@ -33,22 +33,29 @@ class FulltextGambit implements GambitInterface
         // See https://bugs.mysql.com/bug.php?id=74042
         $bit = str_replace('@', '*', $bit);
 
-        $search->getQuery()
-            ->selectRaw('SUBSTRING_INDEX(GROUP_CONCAT(posts.id ORDER BY MATCH(posts.content) AGAINST (?) DESC), \',\', 1) as most_relevant_post_id', [$bit])
+        $query = $search->getQuery();
+        $grammar = $query->getGrammar();
+
+        $query
+            ->selectRaw('SUBSTRING_INDEX(GROUP_CONCAT('.$grammar->wrap('posts.id').' ORDER BY MATCH('.$grammar->wrap('posts.content').') AGAINST (?) DESC), \',\', 1) as most_relevant_post_id', [$bit])
             ->leftJoin('posts', 'posts.discussion_id', '=', 'discussions.id')
             ->where('posts.type', 'comment')
             ->where(function ($query) use ($search) {
                 event(new ScopeModelVisibility(Post::query()->setQuery($query), $search->getActor(), 'view'));
             })
             ->where(function ($query) use ($bit) {
-                $query->whereRaw('MATCH(discussions.title) AGAINST (? IN BOOLEAN MODE)', [$bit])
-                    ->orWhereRaw('MATCH(posts.content) AGAINST (? IN BOOLEAN MODE)', [$bit]);
+                $grammar = $query->getGrammar();
+
+                $query->whereRaw('MATCH('.$grammar->wrap('discussions.title').') AGAINST (? IN BOOLEAN MODE)', [$bit])
+                    ->orWhereRaw('MATCH('.$grammar->wrap('posts.content').') AGAINST (? IN BOOLEAN MODE)', [$bit]);
             })
             ->groupBy('posts.discussion_id');
 
         $search->setDefaultSort(function ($query) use ($bit) {
-            $query->orderByRaw('MATCH(discussions.title) AGAINST (?) desc', [$bit]);
-            $query->orderByRaw('MATCH(posts.content) AGAINST (?) desc', [$bit]);
+            $grammar = $query->getGrammar();
+
+            $query->orderByRaw('MATCH('.$grammar->wrap('discussions.title').') AGAINST (?) desc', [$bit]);
+            $query->orderByRaw('MATCH('.$grammar->wrap('posts.content').') AGAINST (?) desc', [$bit]);
         });
     }
 }
diff --git a/framework/core/src/Post/Post.php b/framework/core/src/Post/Post.php
index 137e9657d..899949a6d 100644
--- a/framework/core/src/Post/Post.php
+++ b/framework/core/src/Post/Post.php
@@ -121,13 +121,9 @@ class Post extends AbstractModel
 
         // Make sure the post's discussion is visible as well
         $query->whereExists(function ($query) use ($actor) {
-            $grammar = $query->getGrammar();
-            $column1 = $grammar->wrap('discussions.id');
-            $column2 = $grammar->wrap('posts.discussion_id');
-
             $query->selectRaw('1')
                 ->from('discussions')
-                ->whereRaw("$column1 = $column2");
+                ->whereColumn('discussions.id', 'posts.discussion_id');
 
             static::$dispatcher->dispatch(
                 new ScopeModelVisibility(Discussion::query()->setQuery($query), $actor, 'view')
diff --git a/framework/core/src/Post/PostPolicy.php b/framework/core/src/Post/PostPolicy.php
index 34df19747..0ed52e9d1 100644
--- a/framework/core/src/Post/PostPolicy.php
+++ b/framework/core/src/Post/PostPolicy.php
@@ -86,7 +86,7 @@ class PostPolicy extends AbstractPolicy
                     ->orWhereExists(function ($query) use ($actor) {
                         $query->selectRaw('1')
                             ->from('discussions')
-                            ->whereRaw('discussions.id = posts.discussion_id')
+                            ->whereColumn('discussions.id', 'posts.discussion_id')
                             ->where(function ($query) use ($actor) {
                                 $this->events->dispatch(
                                     new ScopeModelVisibility(Discussion::query()->setQuery($query), $actor, 'hidePosts')