fix: set allow filter_select for Query objects in Explore (#20754)

* set allow filter select

* add small comment

* add better logic

* remove condition and reference it in backend

superset/models/helpers.py

@@ -1189,6 +1189,38 @@ class ExploreMixin:  # pylint: disable=too-many-public-methods
 
         return or_(*groups)
 
+    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.
+        """
+        cols = {}
+        for col in self.columns:
+            if isinstance(col, dict):
+                cols[col.get("column_name")] = col
+            else:
+                cols[col.column_name] = col
+
+        target_col = cols[column_name]
+        tp = None  # todo(hughhhh): add back self.get_template_processor()
+        tbl, cte = self.get_from_clause(tp)
+
+        if isinstance(target_col, dict):
+            sql_column = sa.column(target_col.get("name"))
+        else:
+            sql_column = target_col
+
+        qry = sa.select([sql_column]).select_from(tbl).distinct()
+        if limit:
+            qry = qry.limit(limit)
+
+        engine = self.database.get_sqla_engine()
+        sql = qry.compile(engine, compile_kwargs={"literal_binds": True})
+        sql = self._apply_cte(sql, cte)
+        sql = self.mutate_query_from_config(sql)
+
+        df = pd.read_sql_query(sql=sql, con=engine)
+        return df[column_name].to_list()
+
     def get_sqla_query(  # pylint: disable=too-many-arguments,too-many-locals,too-many-branches,too-many-statements
         self,
         apply_fetch_values_predicate: bool = False,

superset/models/sql_lab.py

@@ -212,6 +212,7 @@ class Query(Model, ExtraJSONMixin, ExploreMixin):  # pylint: disable=abstract-me
     @property
     def data(self) -> Dict[str, Any]:
         return {
+            "filter_select": True,
             "name": self.tab_name,
             "columns": self.columns,
             "metrics": [],