From 5a1f462b18b795f1ff0b81e98e587bb7069ff8dd Mon Sep 17 00:00:00 2001
From: nifinity <75512822@qq.com>
Date: Thu, 6 Aug 2020 16:10:40 +0800
Subject: [PATCH 1/2] varchar len modify

---
 src/common/backend/catalog/system_views.sql |  4 ++--
 src/common/backend/utils/adt/varchar.cpp    |  6 ++++++
 src/test/regress/expected/varchar.out       | 12 ++++++++++++
 src/test/regress/sql/varchar.sql            |  4 ++++
 4 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/common/backend/catalog/system_views.sql b/src/common/backend/catalog/system_views.sql
index 760df349f7..e34f8f79ec 100644
--- a/src/common/backend/catalog/system_views.sql
+++ b/src/common/backend/catalog/system_views.sql
@@ -1656,8 +1656,8 @@ AS $$ SELECT CAST(float8out($1) AS VARCHAR2) $$
 LANGUAGE SQL  STRICT IMMUTABLE NOT FENCED;
 
 CREATE OR REPLACE FUNCTION to_char(TEXT)
-RETURNS TEXT
-AS $$ SELECT $1 $$
+RETURNS varchar
+AS $$ SELECT $1::varchar(10485760) $$
 LANGUAGE SQL  STRICT IMMUTABLE NOT FENCED;
 
 CREATE OR REPLACE FUNCTION to_number(TEXT)
diff --git a/src/common/backend/utils/adt/varchar.cpp b/src/common/backend/utils/adt/varchar.cpp
index f36e493198..b3298d0bbb 100755
--- a/src/common/backend/utils/adt/varchar.cpp
+++ b/src/common/backend/utils/adt/varchar.cpp
@@ -572,6 +572,12 @@ Datum varchar(PG_FUNCTION_ARGS)
 
     /* only reach here if string is too long... */
 
+    if (len > MaxAttrSize) {
+        ereport(ERROR,
+            (errcode(ERRCODE_STRING_DATA_RIGHT_TRUNCATION),
+                errmsg("value too long for type character varying maxlen(%d) input_len(%d)", MaxAttrSize, len)));
+    }
+
     /* truncate multibyte string preserving multibyte boundary */
     max_mb_len = pg_mbcharcliplen(s_data, len, max_len);
 
diff --git a/src/test/regress/expected/varchar.out b/src/test/regress/expected/varchar.out
index dc6474cc29..e088e15dae 100644
--- a/src/test/regress/expected/varchar.out
+++ b/src/test/regress/expected/varchar.out
@@ -108,3 +108,15 @@ SELECT '' AS four, * FROM VARCHAR_TBL ORDER BY f1;
       | abcd
 (4 rows)
 
+
+select char_length(to_char(lpad('abc', 1024 * 1024 *10, 'x')));
+ char_length 
+-------------
+    10485760
+(1 row)
+
+select char_length(to_char(lpad('abc', 1024 * 1024 *10 + 1, 'x')));
+ERROR:  value too long for type character varying maxlen(10485760) input_len(10485761)
+CONTEXT:  referenced column: varchar
+SQL function "to_char" statement 1
+referenced column: char_length
\ No newline at end of file
diff --git a/src/test/regress/sql/varchar.sql b/src/test/regress/sql/varchar.sql
index f6daf1acaf..7cfbb6bde8 100644
--- a/src/test/regress/sql/varchar.sql
+++ b/src/test/regress/sql/varchar.sql
@@ -64,3 +64,7 @@ INSERT INTO VARCHAR_TBL (f1) VALUES ('abcde');
 INSERT INTO VARCHAR_TBL (f1) VALUES ('abcd    ');
 
 SELECT '' AS four, * FROM VARCHAR_TBL ORDER BY f1;
+
+select char_length(to_char(lpad('abc', 1024 * 1024 *10, 'x')));
+
+select char_length(to_char(lpad('abc', 1024 * 1024 *10 + 1, 'x')));
-- 
Gitee


From adb753db88e8c618f930fc0c492c09b753cc7ee9 Mon Sep 17 00:00:00 2001
From: nifinity <75512822@qq.com>
Date: Thu, 6 Aug 2020 16:47:46 +0800
Subject: [PATCH 2/2] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E7=A9=BA=E6=A0=BC?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/test/regress/expected/varchar.out | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/test/regress/expected/varchar.out b/src/test/regress/expected/varchar.out
index e088e15dae..2759e06a24 100644
--- a/src/test/regress/expected/varchar.out
+++ b/src/test/regress/expected/varchar.out
@@ -108,7 +108,6 @@ SELECT '' AS four, * FROM VARCHAR_TBL ORDER BY f1;
       | abcd
 (4 rows)
 
-
 select char_length(to_char(lpad('abc', 1024 * 1024 *10, 'x')));
  char_length 
 -------------
-- 
Gitee