diff --git a/src/main/java/com/alibaba/druid/pool/vendor/PGValidConnectionChecker.java b/src/main/java/com/alibaba/druid/pool/vendor/PGValidConnectionChecker.java
index 465ff55fef..0bbc71fd8d 100644
--- a/src/main/java/com/alibaba/druid/pool/vendor/PGValidConnectionChecker.java
+++ b/src/main/java/com/alibaba/druid/pool/vendor/PGValidConnectionChecker.java
@@ -35,7 +35,7 @@ public class PGValidConnectionChecker extends ValidConnectionCheckerAdapter impl
 
     private static final Log  LOG                  = LogFactory.getLog(PGValidConnectionChecker.class);
 
-    private String            defaultValidateQuery = "SELECT 'x' FROM DUAL";
+    private String            defaultValidateQuery = "SELECT 'x'";
 
     public PGValidConnectionChecker(){
         configFromProperties(System.getProperties());