v47-0001-replace-some-AST-to-clause.nocfbot

From 956d0d13c5705a5c445d9df71117d2a6f4b1904f Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Fri, 12 Jun 2026 11:30:25 +0800
Subject: [PATCH v47 1/6] replace some AST to clause

---
 src/backend/executor/README.rpr | 4 ++--
 src/backend/parser/parse_rpr.c  | 5 ++---
 src/include/nodes/parsenodes.h  | 9 ++++-----
 3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/backend/executor/README.rpr b/src/backend/executor/README.rpr
index 00af86681b..e913e192b2 100644
--- a/src/backend/executor/README.rpr
+++ b/src/backend/executor/README.rpr
@@ -98,10 +98,10 @@ RPR processing is divided into three phases:
 
   +------------------------------------------------------------+
   |  1. Parsing (Parser)                                       |
-  |     SQL text -> PATTERN AST + DEFINE expression tree       |
+  |     SQL text -> PATTERN clause + DEFINE expression tree       |
   |                                                            |
   |  2. Compilation (Optimizer/Planner)                        |
-  |     PATTERN AST -> optimization -> flat NFA element array  |
+  |     PATTERN clause -> optimization -> flat NFA element array  |
   |                                                            |
   |  3. Execution (Executor)                                   |
   |     Row-by-row matching via NFA simulation                 |
diff --git a/src/backend/parser/parse_rpr.c b/src/backend/parser/parse_rpr.c
index 3eaea2be75..a21aadae73 100644
--- a/src/backend/parser/parse_rpr.c
+++ b/src/backend/parser/parse_rpr.c
@@ -8,7 +8,7 @@
  *   - Validates frame options (must start at CURRENT ROW, no EXCLUDE)
  *   - Validates PATTERN variable count (max RPR_VARID_MAX + 1)
  *   - Transforms DEFINE clause
- *   - Stores the PATTERN AST and the SKIP TO/INITIAL flags
+ *   - Stores the PATTERN clause and the SKIP TO/INITIAL flags
  *
  * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
@@ -67,7 +67,7 @@ static bool define_walker(Node *node, void *context);
  *   - Set AFTER MATCH SKIP TO flag
  *   - Set SEEK/INITIAL flag
  *   - Transforms DEFINE clause into TargetEntry list
- *   - Stores PATTERN AST for deparsing (optimization happens in planner)
+ *   - Stores PATTERN clause
  *
  * Returns early if windef has no rpCommonSyntax (non-RPR window).
  */
@@ -180,7 +180,6 @@ transformRPR(ParseState *pstate, WindowClause *wc, WindowDef *windef,
 	/* Transform DEFINE clause into list of TargetEntry's */
 	wc->defineClause = transformDefineClause(pstate, wc, windef, targetlist);
 
-	/* Store PATTERN AST for deparsing */
 	wc->rpPattern = windef->rpCommonSyntax->rpPattern;
 }
 
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 3266c11a71..f210ee08ed 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -619,7 +619,7 @@ typedef enum RPRPatternNodeType
 } RPRPatternNodeType;
 
 /*
- * RPRPatternNode - Row Pattern Recognition pattern AST node
+ * RPRPatternNode - Row Pattern Recognition PATTER clause
  */
 typedef struct RPRPatternNode
 {
@@ -650,7 +650,7 @@ typedef struct RPCommonSyntax
 	RPSkipTo	rpSkipTo;		/* Row Pattern AFTER MATCH SKIP type */
 	bool		initial;		/* true if <row pattern initial or seek> is
 								 * initial */
-	RPRPatternNode *rpPattern;	/* PATTERN clause AST */
+	RPRPatternNode *rpPattern;	/* PATTERN clause */
 	List	   *rpDefs;			/* row pattern definitions clause (list of
 								 * ResTarget) */
 	ParseLoc	location;		/* PATTERN keyword location, or -1 */
@@ -1728,8 +1728,7 @@ typedef struct GroupingSet
  *
  * "defineClause" is Row Pattern Recognition DEFINE clause (list of
  * TargetEntry). TargetEntry.resname represents row pattern definition
- * variable name. "rpPattern" represents PATTERN clause as an AST tree
- * (RPRPatternNode).
+ * variable name. "rpPattern" represents the PATTERN clause.
  *
  * The information relevant for the query jumbling is the partition clause
  * type and its bounds.
@@ -1766,7 +1765,7 @@ typedef struct WindowClause
 								 * initial */
 	/* Row Pattern DEFINE clause (list of TargetEntry) */
 	List	   *defineClause;
-	/* Row Pattern PATTERN clause AST */
+	/* Row Pattern PATTERN clause */
 	RPRPatternNode *rpPattern;
 } WindowClause;
 
-- 
2.34.1