Update comments on CustomPath struct.

Commit e7cb7ee14 allowed custom scan providers to create CustomPath
paths for join relations as well, but missed updating the comments.

Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAPmGK15ODkN%2B%3DhkBCufj1HBW0x5OTb65Xuy7ryXchMdiCMpx_g%40mail.gmail.com

diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h
index c6585714182f8ccc27915a7fa567bfa56e0f1b35..b1884c74fd2f0baddbc90016f6d64939857100a2 100644 (file)
--- a/src/include/nodes/relation.h
+++ b/src/include/nodes/relation.h
@@ -1269,15 +1269,18 @@ typedef struct ForeignPath
 } ForeignPath;
 
 /*
- * CustomPath represents a table scan done by some out-of-core extension.
+ * CustomPath represents a table scan or a table join done by some out-of-core
+ * extension.
  *
  * We provide a set of hooks here - which the provider must take care to set
  * up correctly - to allow extensions to supply their own methods of scanning
- * a relation.  For example, a provider might provide GPU acceleration, a
- * cache-based scan, or some other kind of logic we haven't dreamed up yet.
+ * a relation or joing relations.  For example, a provider might provide GPU
+ * acceleration, a cache-based scan, or some other kind of logic we haven't
+ * dreamed up yet.
  *
- * CustomPaths can be injected into the planning process for a relation by
- * set_rel_pathlist_hook functions.
+ * CustomPaths can be injected into the planning process for a base or join
+ * relation by set_rel_pathlist_hook or set_join_pathlist_hook functions,
+ * respectively.
  *
  * Core code must avoid assuming that the CustomPath is only as large as
  * the structure declared here; providers are allowed to make it the first