diff --git a/src/Oci8/Schema/Grammars/OracleGrammar.php b/src/Oci8/Schema/Grammars/OracleGrammar.php
index 27d7c291..ab982e1c 100644
--- a/src/Oci8/Schema/Grammars/OracleGrammar.php
+++ b/src/Oci8/Schema/Grammars/OracleGrammar.php
@@ -266,7 +266,7 @@ public function compileForeign(Blueprint $blueprint, Fluent $command)
      */
     public function compileUnique(Blueprint $blueprint, Fluent $command)
     {
-        $columns =  array_map(function($column) {
+        $columns =  array_map(function ($column) {
             $column = $this->wrap($column);
 
             return "lower({$column})";