Fixed #26285 -- Deprecated the MySQL-specific __search lookup.

docs/releases/1.10.txt

@@ -740,6 +740,28 @@ use the default_related_name ``bars``::
 
     >>> Foo.object.get(bars=bar)
 
+.. _search-lookup-replacement:
+
+``__search`` query lookup
+-------------------------
+
+The ``search`` lookup, which supports MySQL only and is extremely limited in
+features, is deprecated. Replace it with a custom lookup::
+
+    from django.db import models
+
+    class Search(models.Lookup):
+        lookup_name = 'search'
+
+        def as_mysql(self, compiler, connection):
+            lhs, lhs_params = self.process_lhs(compiler, connection)
+            rhs, rhs_params = self.process_rhs(compiler, connection)
+            params = lhs_params + rhs_params
+            return 'MATCH (%s) AGAINST (%s IN BOOLEAN MODE)' % (lhs, rhs), params
+
+    models.CharField.register_lookup(Search)
+    models.TextField.register_lookup(Search)
+
 Miscellaneous
 -------------