From 7dd0f3829cba1db6aff18090e1185d1fe5553e95 Mon Sep 17 00:00:00 2001
From: Zizhuan Liu <44973863@qq.com>
Date: Wed, 17 Jun 2026 18:29:52 +0800
Subject: [PATCH v2] Improving psql autocompletion for SET LOCAL / SET SESSION
 v2

---
 src/bin/psql/tab-complete.in.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c
index de547a8c..47b842c6 100644
--- a/src/bin/psql/tab-complete.in.c
+++ b/src/bin/psql/tab-complete.in.c
@@ -1243,6 +1243,10 @@ Copy_common_options, "DEFAULT", "FORCE_NOT_NULL", "FORCE_NULL", "FREEZE", \
 #define Copy_to_options \
 Copy_common_options, "FORCE_QUOTE", "FORCE_ARRAY"
 
+/* SET special parameters  */
+#define Set_special_parameters \
+"SCHEMA", "NAMES", "SEED", "TIME ZONE"
+
 /*
  * These object types were introduced later than our support cutoff of
  * server version 9.2.  We use the VersionedQuery infrastructure so that
@@ -5280,16 +5284,21 @@ match_previous_words(int pattern_id,
 
 /* SET, RESET, SHOW */
 	/* Complete with a variable name */
-	else if (TailMatches("SET|RESET") &&
-			 !TailMatches("UPDATE", MatchAny, "SET") &&
+	else if (TailMatches("RESET") &&
 			 !TailMatches("ALTER", "DATABASE|USER|ROLE", MatchAny, "RESET"))
+		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
+										  "ALL");
+	else if (TailMatches("SET") &&
+			 !TailMatches("UPDATE", MatchAny, "SET"))
 		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
 										  "CONSTRAINTS",
 										  "TRANSACTION",
 										  "SESSION",
 										  "ROLE",
 										  "TABLESPACE",
-										  "ALL");
+										  "LOCAL",
+										  "SESSION",
+										  Set_special_parameters);
 	else if (Matches("SHOW"))
 		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_show_vars,
 										  "SESSION AUTHORIZATION",
@@ -5335,12 +5344,19 @@ match_previous_words(int pattern_id,
 	/* Complete SET CONSTRAINTS <foo> with DEFERRED|IMMEDIATE */
 	else if (Matches("SET", "CONSTRAINTS", MatchAny))
 		COMPLETE_WITH("DEFERRED", "IMMEDIATE");
+	/* Complete SET LOCAL with a variable name */
+	else if (Matches("SET", "LOCAL"))
+		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
+										  Set_special_parameters);
 	/* Complete SET ROLE */
 	else if (Matches("SET", "ROLE"))
 		COMPLETE_WITH_QUERY(Query_for_list_of_roles);
-	/* Complete SET SESSION with AUTHORIZATION or CHARACTERISTICS... */
+	/* Complete SET SESSION with a variable name */
 	else if (Matches("SET", "SESSION"))
-		COMPLETE_WITH("AUTHORIZATION", "CHARACTERISTICS AS TRANSACTION");
+		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
+										  Set_special_parameters,
+										  "AUTHORIZATION",
+										  "CHARACTERISTICS AS TRANSACTION");
 	/* Complete SET SESSION AUTHORIZATION with username */
 	else if (Matches("SET", "SESSION", "AUTHORIZATION"))
 		COMPLETE_WITH_QUERY_PLUS(Query_for_list_of_roles,
-- 
2.43.0