diff --git a/include/QueryGenerator/QueryGenerator.php b/include/QueryGenerator/QueryGenerator.php
index b5bbd0f9d424fe8ba590a955b19ede523999f148..f97b0cd44cf23f03a0a83b1a4ed718532d925371 100644
--- a/include/QueryGenerator/QueryGenerator.php
+++ b/include/QueryGenerator/QueryGenerator.php
@@ -1194,7 +1194,10 @@ class QueryGenerator {
                         if( ($field->getFieldDataType() != 'birthday' || ($field->getFieldDataType() == 'birthday'
                                         && $this->isRelativeSearchOperators($operator)))){
                             if($field->getFieldDataType() !== 'integer'){
-                                $value = "'$value'";
+								$pattern = '/^[a-zA-Z0-9_]+$/';
+								if(preg_match($pattern,$value)){
+									$value="'$value'";
+								}
                             }
                         }