fix: excel sheet upload is not working (#10450)

* remove conflicts with csv upload

* revert StringField

* change description

* remove redundant space

* apply string approach

superset/views/database/views.py

@@ -263,10 +263,9 @@ class ExcelToDatabaseView(SimpleFormView):
     def form_get(self, form: ExcelToDatabaseForm) -> None:
         form.header.data = 0
         form.mangle_dupe_cols.data = True
-        form.skipinitialspace.data = False
         form.decimal.data = "."
         form.if_exists.data = "fail"
-        form.sheet_name = None
+        form.sheet_name.data = ""
 
     def form_post(self, form: ExcelToDatabaseForm) -> Response:
         database = form.con.data
@@ -307,16 +306,23 @@ class ExcelToDatabaseView(SimpleFormView):
             database = (
                 db.session.query(models.Database).filter_by(id=con.data.get("id")).one()
             )
+
+            # some params are not supported by pandas.read_excel (e.g. chunksize).
+            # More can be found here:
+            # https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.read_excel.html
             excel_to_df_kwargs = {
                 "header": form.header.data if form.header.data else 0,
                 "index_col": form.index_col.data,
                 "mangle_dupe_cols": form.mangle_dupe_cols.data,
-                "skipinitialspace": form.skipinitialspace.data,
                 "skiprows": form.skiprows.data,
                 "nrows": form.nrows.data,
-                "sheet_name": form.sheet_name.data,
-                "chunksize": 1000,
+                "sheet_name": form.sheet_name.data if form.sheet_name.data else 0,
+                "parse_dates": form.parse_dates.data,
             }
+            if form.null_values.data:
+                excel_to_df_kwargs["na_values"] = form.null_values.data
+                excel_to_df_kwargs["keep_default_na"] = False
+
             df_to_sql_kwargs = {
                 "name": excel_table.table,
                 "if_exists": form.if_exists.data,
@@ -336,7 +342,7 @@ class ExcelToDatabaseView(SimpleFormView):
             # E.g. if hive was used to upload a excel, presto will be a better option
             # to explore the table.
             expore_database = database
-            explore_database_id = database.get_extra().get("explore_database_id", None)
+            explore_database_id = database.explore_database_id
             if explore_database_id:
                 expore_database = (
                     db.session.query(models.Database)