PostgreSQL full-text search in the Django Admin

Author: simonw

django/postgresql-full-text-search-admin.md

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+# PostgreSQL full-text search in the Django Admin
+
+Django 3.1 introduces PostgreSQL `search_type="websearch"` - which gives you search with advanced operators like `"phrase search" -excluding`. James Turk [wrote about this here](https://jamesturk.net/posts/websearch-in-django-31/), and it's also in [my weeknotes](https://simonwillison.net/2020/Jul/23/datasette-copyable-datasette-insert-api/).
+
+I decided to add it to my Django Admin interface. It was _really easy_ using the `get_search_results()` model admin method, [documented here](https://docs.djangoproject.com/en/3.0/ref/contrib/admin/#django.contrib.admin.ModelAdmin.get_search_results).
+
+My models already have a `search_document` full-text search column, as described in [Implementing faceted search with Django and PostgreSQL](https://simonwillison.net/2017/Oct/5/django-postgresql-faceted-search/). So all I needed to add to my `ModelAdmin` subclasses was this:
+
+```python
+    def get_search_results(self, request, queryset, search_term):
+        if not search_term:
+            return super().get_search_results(
+                request, queryset, search_term
+            )
+        query = SearchQuery(search_term, search_type="websearch")
+        rank = SearchRank(F("search_document"), query)
+        queryset = (
+            queryset
+            .annotate(rank=rank)
+            .filter(search_document=query)
+            .order_by("-rank")
+        )
+        return queryset, False
+```
+Here's [the full implementation](https://github.com/simonw/simonwillisonblog/blob/6c0de9f9976ef831fe92106be662d77dfe80b32a/blog/admin.py) for my personal blog.