diff --git a/mario/query_builder.py b/mario/query_builder.py
index 1dd3c03..c5110c9 100644
--- a/mario/query_builder.py
+++ b/mario/query_builder.py
@@ -8,6 +8,7 @@
 from mario.dataset_specification import DatasetSpecification
 from mario.metadata import Metadata
 from mario.mapping import FieldMapping
+from mario.utils import to_snake_case
 
 logger = logging.getLogger(__name__)
 
@@ -172,7 +173,7 @@ def create_constraints(self, q):
             column = self.mapping.as_physical[constraint.item]
             placeholders = []
             for i in range(len(constraint.allowed_values)):
-                parameter_name = column.replace(" ", "_") + str(i)
+                parameter_name = to_snake_case(column) + str(i)
                 # Postgres style.
                 # TODO Probably need some way of identifying which parameter style to apply.
                 parameter = Parameter('%('+parameter_name+')s')
diff --git a/setup.py b/setup.py
index 310aff7..24a3869 100644
--- a/setup.py
+++ b/setup.py
@@ -2,7 +2,7 @@
 
 setup(
     name='mario-pipeline-tools',
-    version='0.62',
+    version='0.63',
     packages=['mario'],
     url='https://github.com/JiscDACT/mario',
     license='all rights reserved',