diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index 70e48de9400076f327d248e1b0ecdf7d1dc0fed6..6bda8888b7338d9c332f70bd8cf3e8584f6b70fb 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -1015,6 +1015,12 @@ def prevent_writes=(prevent_writes) # :nodoc:
       # In some cases you may want to prevent writes to the database
       # even if you are on a database that can write. `while_preventing_writes`
       # will prevent writes to the database for the duration of the block.
+      #
+      # This method does not provide the same protection as a readonly
+      # user and is meant to be a safeguard against accidental writes.
+      #
+      # See `READ_QUERY` for the queries that are blocked by this
+      # method.
       def while_preventing_writes(enabled = true)
         original, self.prevent_writes = self.prevent_writes, enabled
         yield