Postgres Database Import failing on zero-length identifier using btree ("") (Drupal)

Question

Postgres database problem: I'm trying to import a Postgresql 10 database from a working* Drupal 8 installation and I'm stuck on this type of error:

Error in query: ERROR: zero-length delimited identifier at or near """" LINE 1: ...ON "public"."drupal_menu_link_content_data" USING btree ("")

There are about ten of these instances of empty btree index fields:

CREATE INDEX "shortcut_field_data__shortcut_field_link_uri__idx" ON "public"."shortcut_field_data" USING btree ("");

Before I export the database, how can I safely have Drupal supply something to satisfy those fields?

*Or, what else is wrong? (edited)

The full empty label list is here:

CREATE INDEX "drupal_QnV_yx12IV6LUDK8fiqQScOLltRLWh6lj73Z_u1PXWY_idx" ON "public"."drupal_menu_link_content_field_revision" USING btree ("");

CREATE INDEX "drupal_node__field_app_url__field_app_url_uri__idx" ON "public"."drupal_node__field_app_url" USING btree ("");

CREATE INDEX "drupal_node__field_url__field_url_uri__idx" ON "public"."drupal_node__field_url" USING btree ("");

CREATE INDEX "drupal_node__field_url__field_url_uri__idx" ON "public"."drupal_node__field_url" USING btree ("");

CREATE INDEX "drupal_node_revision__field_app_url__field_app_url_uri__idx" ON "public"."drupal_node_revision__field_app_url" USING btree ("");

CREATE INDEX "drupal_node_revision__field_url__field_url_uri__idx" ON "public"."drupal_node_revision__field_url" USING btree ("");

CREATE INDEX "drupal_shortcut_field_data__shortcut_field__link__uri__idx" ON "public"."drupal_shortcut_field_data" USING btree ("");

CREATE INDEX "menu_link_content_data__menu_link_content_field__link__uri__idx" ON "public"."menu_link_content_data" USING btree ("");

CREATE INDEX "drupal_ui7U_4ySVsbBkDhd7CC2Cz97Yr_s3QEuF9xZI0mi1lA_idx" ON "public"."menu_link_content_field_revision" USING btree ("");

CREATE INDEX "shortcut_field_data__shortcut_field__link__uri__idx" ON "public"."shortcut_field_data" USING btree ("");

They all seem to have links or urls as a common element. But some are nodes, nore references, and then a menu.