From 47f2cb5c01c7b40a9c6cba57360ea5accea8bd78 Mon Sep 17 00:00:00 2001
From: zhouxiongjia <719216473@qq.com>
Date: Thu, 3 Sep 2020 20:19:11 +0800
Subject: [PATCH] Ban ROWNUM when creating index.

---
 src/common/backend/parser/parse_utilcmd.cpp |  1 +
 src/test/regress/expected/create_index.out  | 12 ++++++++++++
 src/test/regress/sql/create_index.sql       |  4 ++++
 3 files changed, 17 insertions(+)

diff --git a/src/common/backend/parser/parse_utilcmd.cpp b/src/common/backend/parser/parse_utilcmd.cpp
index 1aaa60f6f..2040dbd18 100644
--- a/src/common/backend/parser/parse_utilcmd.cpp
+++ b/src/common/backend/parser/parse_utilcmd.cpp
@@ -3265,6 +3265,7 @@ IndexStmt* transformIndexStmt(Oid relid, IndexStmt* stmt, const char* queryStrin
              * consistency with what transformWhereClause() checks for the
              * predicate.  DefineIndex() will make more checks.
              */
+			ExcludeRownumExpr(pstate, (Node*)ielem->expr);
             if (expression_returns_set(ielem->expr))
                 ereport(ERROR, (errcode(ERRCODE_DATATYPE_MISMATCH), errmsg("index expression cannot return a set")));
         }
diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index d9eb20283..cb594d0bf 100644
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -2721,6 +2721,18 @@ explain (costs off) select  /*+ rows(t_rep_table #100000) */  * from t_hash_tabl
          Index Cond: (a = t_hash_table.a)
 (4 rows)
 
+create index test0 on t_rep_table(rownum);
+ERROR:  specified ROWNUM is not allowed here.
+LINE 1: create index test0 on t_rep_table(rownum);
+                                          ^
+create index test0 on t_rep_table(sin(a), sin(rownum));
+ERROR:  specified ROWNUM is not allowed here.
+LINE 1: create index test0 on t_rep_table(sin(a), sin(rownum));
+                                                  ^
+create index test0 on t_rep_table(sin(a), sin(rownum+1));
+ERROR:  specified ROWNUM is not allowed here.
+LINE 1: create index test0 on t_rep_table(sin(a), sin(rownum+1));
+                                                  ^
 drop index idx_rep_table;
 drop table t_hash_table;
 drop table t_rep_table;
diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index 690e47ce4..25c9bf2b5 100644
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -956,6 +956,10 @@ create index idx_rep_table on t_rep_table(a);
 explain (costs off) select  /*+ rows(t_rep_table #100000) */  * from t_hash_table where t_hash_table.a in (select a from t_rep_table);
 explain (costs off) select  /*+ rows(t_rep_table #100000) */  * from t_hash_table where '1' = '0' or t_hash_table.a in (select a from t_rep_table);
 
+create index test0 on t_rep_table(rownum);
+create index test0 on t_rep_table(sin(a), sin(rownum));
+create index test0 on t_rep_table(sin(a), sin(rownum+1));
+
 drop index idx_rep_table;
 drop table t_hash_table;
 drop table t_rep_table;