diff --git a/superset/assets/javascripts/explorev2/components/controls/Filter.jsx b/superset/assets/javascripts/explorev2/components/controls/Filter.jsx
index 3397ded94..9e783fc62 100644
--- a/superset/assets/javascripts/explorev2/components/controls/Filter.jsx
+++ b/superset/assets/javascripts/explorev2/components/controls/Filter.jsx
@@ -100,9 +100,6 @@ export default class Filter extends React.Component {
     // switching filter value between array/string when needed
     if (strFilterOps.indexOf(filter.op) !== -1) {
       // druid having filter or regex/==/!= filters
-      if (typeof filter.val !== 'string') {
-        this.props.changeFilter('val', filter.val.length > 0 ? filter.val[0] : '');
-      }
       return (
         <input
           type="text"
@@ -113,9 +110,6 @@ export default class Filter extends React.Component {
         />
       );
     }
-    if (typeof filter.val === 'string') {
-      this.props.changeFilter('val', filter.val === '' ? [] : [filter.val]);
-    }
     return (
       <SelectControl
         multi
diff --git a/superset/models.py b/superset/models.py
index cd3ed4d25..c37884230 100644
--- a/superset/models.py
+++ b/superset/models.py
@@ -2579,6 +2579,8 @@ class DruidDatasource(Model, AuditMixinNullable, Datasource, ImportMixin):
             cond = None
             if op in ('in', 'not in'):
                 eq = [types.replace("'", '').strip() for types in eq]
+            elif not isinstance(flt['val'], basestring):
+                eq = eq[0] if len(eq) > 0 else ''
             if col in self.num_cols:
                 if op in ('in', 'not in'):
                     eq = [utils.js_string_to_num(v) for v in eq]