fix: null value and empty string in filter

superset-frontend/src/explore/components/controls/FilterControl/AdhocFilterEditPopoverSimpleTabContent/index.tsx

@@ -38,6 +38,7 @@ import AdhocFilter, {
 } from 'src/explore/components/controls/FilterControl/AdhocFilter';
 import { Input } from 'src/common/components';
 import { propertyComparator } from 'src/components/Select/Select';
+import { optionLabel } from 'src/utils/common';
 
 const StyledInput = styled(Input)`
   margin-bottom: ${({ theme }) => theme.gridUnit * 4}px;
@@ -226,7 +227,9 @@ const AdhocFilterEditPopoverSimpleTabContent: React.FC<Props> = props => {
     isOperatorRelevant,
     onComparatorChange,
   } = useSimpleTabFilterProps(props);
-  const [suggestions, setSuggestions] = useState<Record<string, any>>([]);
+  const [suggestions, setSuggestions] = useState<
+    Record<'label' | 'value', any>[]
+  >([]);
   const [comparator, setComparator] = useState(props.adhocFilter.comparator);
   const [loadingComparatorSuggestions, setLoadingComparatorSuggestions] =
     useState(false);
@@ -346,7 +349,12 @@ const AdhocFilterEditPopoverSimpleTabContent: React.FC<Props> = props => {
           endpoint: `/superset/filter/${datasource.type}/${datasource.id}/${col}/`,
         })
           .then(({ json }) => {
-            setSuggestions(json);
+            setSuggestions(
+              json.map((suggestion: null | number | boolean | string) => ({
+                value: suggestion,
+                label: optionLabel(suggestion),
+              })),
+            );
             setLoadingComparatorSuggestions(false);
           })
           .catch(() => {
@@ -402,10 +410,7 @@ const AdhocFilterEditPopoverSimpleTabContent: React.FC<Props> = props => {
       {MULTI_OPERATORS.has(operatorId) || suggestions.length > 0 ? (
         <SelectWithLabel
           labelText={labelText}
-          options={suggestions.map((suggestion: string) => ({
-            value: suggestion,
-            label: String(suggestion),
-          }))}
+          options={suggestions}
           {...comparatorSelectProps}
           sortComparator={propertyComparator(
             typeof suggestions[0] === 'number' ? 'value' : 'label',

superset-frontend/src/explore/exploreUtils/getSimpleSQLExpression.test.ts

@@ -16,7 +16,9 @@
  * specific language governing permissions and limitations
  * under the License.
  */
+import { EMPTY_STRING, NULL_STRING } from 'src/utils/common';
 import { getSimpleSQLExpression } from '.';
+import { Operators } from '../constants';
 
 const params = {
   subject: 'subject',
@@ -36,6 +38,12 @@ test('Should return "" if subject is falsy', () => {
   ).toBe('');
 });
 
+test('Should return null string and empty string', () => {
+  expect(getSimpleSQLExpression(params.subject, Operators.IN, [null, ''])).toBe(
+    `subject ${Operators.IN} (${NULL_STRING}, ${EMPTY_STRING})`,
+  );
+});
+
 test('Should return subject if operator is falsy', () => {
   expect(getSimpleSQLExpression(params.subject, '', params.comparator)).toBe(
     params.subject,

superset-frontend/src/explore/exploreUtils/index.js

@@ -35,6 +35,7 @@ import {
   OPERATOR_ENUM_TO_OPERATOR_TYPE,
 } from 'src/explore/constants';
 import { DashboardStandaloneMode } from 'src/dashboard/util/constants';
+import { optionLabel } from '../../utils/common';
 
 const MAX_URL_LENGTH = 8000;
 
@@ -374,10 +375,12 @@ export const getSimpleSQLExpression = (subject, operator, comparator) => {
       firstValue !== undefined && Number.isNaN(Number(firstValue));
     const quote = isString ? "'" : '';
     const [prefix, suffix] = isMulti ? ['(', ')'] : ['', ''];
-    const formattedComparators = comparatorArray.map(
-      val =>
-        `${quote}${isString ? String(val).replace("'", "''") : val}${quote}`,
-    );
+    const formattedComparators = comparatorArray
+      .map(val => optionLabel(val))
+      .map(
+        val =>
+          `${quote}${isString ? String(val).replace("'", "''") : val}${quote}`,
+      );
     if (comparatorArray.length > 0) {
       expression += ` ${prefix}${formattedComparators.join(', ')}${suffix}`;
     }

superset-frontend/src/utils/common.js

@@ -24,6 +24,7 @@ import {
 
 // ATTENTION: If you change any constants, make sure to also change constants.py
 
+export const EMPTY_STRING = '<empty string>';
 export const NULL_STRING = '<NULL>';
 export const TRUE_STRING = 'TRUE';
 export const FALSE_STRING = 'FALSE';
@@ -61,7 +62,7 @@ export function optionLabel(opt) {
     return NULL_STRING;
   }
   if (opt === '') {
-    return '<empty string>';
+    return EMPTY_STRING;
   }
   if (opt === true) {
     return '<true>';

superset/connectors/base/models.py

@@ -25,7 +25,7 @@
 from sqlalchemy.orm import foreign, Query, relationship, RelationshipProperty, Session
 
 from superset import is_feature_enabled, security_manager
-from superset.constants import NULL_STRING
+from superset.constants import EMPTY_STRING, NULL_STRING
 from superset.datasets.commands.exceptions import DatasetNotFoundError
 from superset.models.helpers import AuditMixinNullable, ImportExportMixin, QueryResult
 from superset.models.slice import Slice
@@ -404,7 +404,7 @@ def handle_single_value(value: Optional[FilterValue]) -> Optional[FilterValue]:
                     return utils.cast_to_num(value)
                 if value == NULL_STRING:
                     return None
-                if value == "<empty string>":
+                if value == EMPTY_STRING:
                     return ""
             if target_column_type == utils.GenericDataType.BOOLEAN:
                 return utils.cast_to_boolean(value)
@@ -439,9 +439,7 @@ def query(self, query_obj: QueryObjectDict) -> QueryResult:
         """
         raise NotImplementedError()
 
-    def values_for_column(
-        self, column_name: str, limit: int = 10000, contain_null: bool = True,
-    ) -> List[Any]:
+    def values_for_column(self, column_name: str, limit: int = 10000) -> List[Any]:
         """Given a column, returns an iterable of distinct values
 
         This is used to populate the dropdown showing a list of

superset/connectors/druid/models.py

@@ -948,9 +948,7 @@ def metrics_and_post_aggs(
         )
         return aggs, post_aggs
 
-    def values_for_column(
-        self, column_name: str, limit: int = 10000, contain_null: bool = True,
-    ) -> List[Any]:
+    def values_for_column(self, column_name: str, limit: int = 10000) -> List[Any]:
         """Retrieve some values for the given column"""
         logger.info(
             "Getting values for columns [{}] limited to [{}]".format(column_name, limit)

superset/connectors/sqla/models.py

@@ -176,9 +176,7 @@ def query(self, query_obj: QueryObjectDict) -> QueryResult:
     def get_query_str(self, query_obj: QueryObjectDict) -> str:
         raise NotImplementedError()
 
-    def values_for_column(
-        self, column_name: str, limit: int = 10000, contain_null: bool = True,
-    ) -> List[Any]:
+    def values_for_column(self, column_name: str, limit: int = 10000) -> List[Any]:
         raise NotImplementedError()
 
 
@@ -738,9 +736,7 @@ def get_fetch_values_predicate(self) -> TextClause:
                 )
             ) from ex
 
-    def values_for_column(
-        self, column_name: str, limit: int = 10000, contain_null: bool = True,
-    ) -> List[Any]:
+    def values_for_column(self, column_name: str, limit: int = 10000) -> List[Any]:
         """Runs query against sqla to retrieve some
         sample values for the given column.
         """
@@ -756,9 +752,6 @@ def values_for_column(
         if limit:
             qry = qry.limit(limit)
 
-        if not contain_null:
-            qry = qry.where(target_col.get_sqla_col().isnot(None))
-
         if self.fetch_values_predicate:
             qry = qry.where(self.get_fetch_values_predicate())
 

superset/constants.py

@@ -21,6 +21,7 @@
 from enum import Enum
 
 NULL_STRING = "<NULL>"
+EMPTY_STRING = "<empty string>"
 
 CHANGE_ME_SECRET_KEY = "CHANGE_ME_TO_A_COMPLEX_RANDOM_SECRET"
 

superset/views/core.py

@@ -921,9 +921,7 @@ def filter(  # pylint: disable=no-self-use
         datasource.raise_for_access()
         row_limit = apply_max_row_limit(config["FILTER_SELECT_ROW_LIMIT"])
         payload = json.dumps(
-            datasource.values_for_column(
-                column_name=column, limit=row_limit, contain_null=False,
-            ),
+            datasource.values_for_column(column_name=column, limit=row_limit),
             default=utils.json_int_dttm_ser,
             ignore_nan=True,
         )

tests/integration_tests/sqla_models_tests.py

@@ -30,7 +30,8 @@
 from sqlalchemy.sql.elements import TextClause
 
 from superset import db
-from superset.connectors.sqla.models import SqlaTable, TableColumn
+from superset.connectors.sqla.models import SqlaTable, TableColumn, SqlMetric
+from superset.constants import EMPTY_STRING, NULL_STRING
 from superset.db_engine_specs.bigquery import BigQueryEngineSpec
 from superset.db_engine_specs.druid import DruidEngineSpec
 from superset.exceptions import QueryObjectValidationError
@@ -477,22 +478,77 @@ def test_labels_expected_on_mutated_query(self):
     def test_values_for_column(self):
         table = SqlaTable(
             table_name="test_null_in_column",
-            sql="SELECT 'foo' as foo UNION SELECT 'bar' UNION SELECT NULL",
+            sql=(
+                "SELECT 'foo' as foo "
+                "UNION SELECT '' "
+                "UNION SELECT NULL "
+                "UNION SELECT 'null'"
+            ),
             database=get_example_database(),
         )
         TableColumn(column_name="foo", type="VARCHAR(255)", table=table)
+        SqlMetric(metric_name="count", expression="count(*)", table=table)
 
-        with_null = table.values_for_column(
-            column_name="foo", limit=10000, contain_null=True
-        )
+        # null value, empty string and text should be retrieved
+        with_null = table.values_for_column(column_name="foo", limit=10000)
         assert None in with_null
-        assert len(with_null) == 3
+        assert len(with_null) == 4
+
+        # null value should be replaced
+        result_object = table.query(
+            {
+                "metrics": ["count"],
+                "filter": [{"col": "foo", "val": [NULL_STRING], "op": "IN"}],
+                "is_timeseries": False,
+            }
+        )
+        assert result_object.df["count"][0] == 1
+
+        # also accept None value
+        result_object = table.query(
+            {
+                "metrics": ["count"],
+                "filter": [{"col": "foo", "val": [None], "op": "IN"}],
+                "is_timeseries": False,
+            }
+        )
+        assert result_object.df["count"][0] == 1
+
+        # empty string should be replaced
+        result_object = table.query(
+            {
+                "metrics": ["count"],
+                "filter": [{"col": "foo", "val": [EMPTY_STRING], "op": "IN"}],
+                "is_timeseries": False,
+            }
+        )
+        assert result_object.df["count"][0] == 1
 
-        without_null = table.values_for_column(
-            column_name="foo", limit=10000, contain_null=False
+        # also accept "" string
+        result_object = table.query(
+            {
+                "metrics": ["count"],
+                "filter": [{"col": "foo", "val": [""], "op": "IN"}],
+                "is_timeseries": False,
+            }
+        )
+        assert result_object.df["count"][0] == 1
+
+        # both replaced
+        result_object = table.query(
+            {
+                "metrics": ["count"],
+                "filter": [
+                    {
+                        "col": "foo",
+                        "val": [EMPTY_STRING, NULL_STRING, "null", "foo"],
+                        "op": "IN",
+                    }
+                ],
+                "is_timeseries": False,
+            }
         )
-        assert None not in without_null
-        assert len(without_null) == 2
+        assert result_object.df["count"][0] == 4
 
 
 @pytest.mark.parametrize(