diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1eaf425..a896004 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 ### Changelog
 
+##### v1.9.8
++ Updated `SelectStatement` class with:
+  - Fixed `getColumns()` method
++ Updated `WhereClause` class with:
+  - Reverted `__toString()` method
++ Updated `HavingClause` class with:
+  - Reverted `__toString()` method
+
 ##### v1.9.7
 + Updated `WhereClause` class with:
   - Fixed some weird bug in `__toString()` method
diff --git a/composer.json b/composer.json
index 80b6888..dca7888 100644
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
     "name": "slim/pdo",
     "description": "PDO database library for Slim Framework",
-    "version": "1.9.7",
+    "version": "1.9.8",
     "type": "library",
     "keywords": ["pdo", "database", "slim", "framework"],
     "homepage": "https://github.com/FaaPz/Slim-PDO",
diff --git a/src/PDO/Clause/HavingClause.php b/src/PDO/Clause/HavingClause.php
index 1a9c1ba..26e9dbb 100644
--- a/src/PDO/Clause/HavingClause.php
+++ b/src/PDO/Clause/HavingClause.php
@@ -102,6 +102,6 @@ public function __toString()
             $args[] = $having;
         }
 
-        return ' HAVING '.ltrim(preg_replace('/AND/', '', implode('', $args)));
+        return ' HAVING '.ltrim(implode('', $args), ' AND');
     }
 }
diff --git a/src/PDO/Clause/WhereClause.php b/src/PDO/Clause/WhereClause.php
index 60e1759..4992ced 100644
--- a/src/PDO/Clause/WhereClause.php
+++ b/src/PDO/Clause/WhereClause.php
@@ -227,6 +227,6 @@ public function __toString()
             $args[] = $where;
         }
 
-        return ' WHERE '.ltrim(preg_replace('/AND/', '', implode('', $args)));
+        return ' WHERE '.ltrim(implode('', $args), ' AND');
     }
 }
diff --git a/src/PDO/Statement/SelectStatement.php b/src/PDO/Statement/SelectStatement.php
index 731450f..43f732e 100644
--- a/src/PDO/Statement/SelectStatement.php
+++ b/src/PDO/Statement/SelectStatement.php
@@ -427,10 +427,6 @@ protected function getSelect()
      */
     protected function getColumns()
     {
-        if ($this->aggregate) {
-            array_splice($this->columns, 0, -1);
-        }
-
         return implode(' , ', $this->columns);
     }