diff --git a/lib/postgis_helper.py b/lib/postgis_helper.py
index 35ffd02aff482be03bd92872859bfe6bb462e218..85fd00838829bcdb11570129149ca34381c98088 100644
--- a/lib/postgis_helper.py
+++ b/lib/postgis_helper.py
@@ -33,8 +33,8 @@ TYPE_PRIORITY_ORDER = (
     )
 
 
-VALID_IP_ADDRESS_REGEX = '(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])'
-VALID_HOSTNAME_ADDRESS = '(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9])'
+VALID_IP_ADDRESS_REGEX = r'(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])'
+VALID_HOSTNAME_ADDRESS = r'(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9])'
 
 
 class Remote(object):
@@ -142,10 +142,10 @@ class Remote(object):
                 for elt in value:
                     return evaluate(elt)
             if isinstance(value, str):
-                if re.match("^\d+?\.\d+?$", value):
+                if re.match(r"^\d+?\.\d+?$", value):
                     # TODO float/double
                     return 'float'
-                elif re.match("^-?(?!0)\d+$", value):
+                elif re.match(r"^-?(?!0)\d+$", value):
                     # TODO short/integer/long
                     return 'int'
                 # TODO: date... ip... binary... object... boolean...