From 3e897bc3b6b838fe4b91d0ee4148d4b6c530c20d Mon Sep 17 00:00:00 2001
From: unknown <hf@deer.(none)>
Date: Fri, 20 Jun 2003 20:04:52 +0500
Subject: [PATCH 1/2] Fix for bug #666 (Nice number, yeah?)

sql/item_strfunc.cc:
  Item_func_elt::valXXX() functions don't expect NULL argument if it is
  not the first one.
---
 sql/item_strfunc.cc | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index 208be1ecd7f..9d4f7641b1d 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -1539,37 +1539,46 @@ void Item_func_elt::update_used_tables()
 double Item_func_elt::val()
 {
   uint tmp;
+  null_value=1;
   if ((tmp=(uint) item->val_int()) == 0 || tmp > arg_count)
-  {
-    null_value=1;
     return 0.0;
-  }
+
+  double result= args[tmp-1]->val();
+  if (args[tmp-1]->is_null())
+    return 0.0;
+
   null_value=0;
-  return args[tmp-1]->val();
+  return result;
 }
 
 longlong Item_func_elt::val_int()
 {
   uint tmp;
+  null_value=1;
   if ((tmp=(uint) item->val_int()) == 0 || tmp > arg_count)
-  {
-    null_value=1;
     return 0;
-  }
+  
+  int result= args[tmp-1]->val_int();
+  if (args[tmp-1]->is_null())
+    return 0;
+
   null_value=0;
-  return args[tmp-1]->val_int();
+  return result;
 }
 
 String *Item_func_elt::val_str(String *str)
 {
   uint tmp;
+  null_value=1;
   if ((tmp=(uint) item->val_int()) == 0 || tmp > arg_count)
-  {
-    null_value=1;
     return NULL;
-  }
+
+  String *result= args[tmp-1]->val_str(str);
+  if (args[tmp-1]->is_null())
+    return NULL;
+
   null_value=0;
-  return args[tmp-1]->val_str(str);
+  return result;
 }
 
 

From 8bed69fa9ec200925d9a9ec36419d2c5eecf9739 Mon Sep 17 00:00:00 2001
From: unknown <hf@deer.(none)>
Date: Tue, 24 Jun 2003 17:07:43 +0500
Subject: [PATCH 2/2] Test case for bug #666

mysql-test/r/func_str.result:
  test for bug #666 result
mysql-test/t/func_str.test:
  test for bug #666
---
 mysql-test/r/func_str.result | 13 +++++++++++++
 mysql-test/t/func_str.test   | 12 ++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/mysql-test/r/func_str.result b/mysql-test/r/func_str.result
index 1a4cb9217e4..09818c14462 100644
--- a/mysql-test/r/func_str.result
+++ b/mysql-test/r/func_str.result
@@ -234,3 +234,16 @@ INSERT INTO t1 VALUES (1, 'a545f661efdd1fb66fdee3aab79945bf');
 SELECT 1 FROM t1 WHERE tmp=AES_DECRYPT(tmp,"password");
 1
 DROP TABLE t1;
+CREATE TABLE t1 (
+wid int(10) unsigned NOT NULL auto_increment,
+data_podp date default NULL,
+status_wnio enum('nowy','podp','real','arch') NOT NULL default 'nowy',
+PRIMARY KEY(wid),
+);
+INSERT INTO t1 VALUES (8,NULL,'real');
+INSERT INTO t1 VALUES (9,NULL,'nowy');
+SELECT elt(status_wnio,data_podp) FROM t1 GROUP BY wid;
+elt(status_wnio,data_podp)
+NULL
+NULL
+DROP TABLE t1;
diff --git a/mysql-test/t/func_str.test b/mysql-test/t/func_str.test
index 118de6cd01e..476629f98d3 100644
--- a/mysql-test/t/func_str.test
+++ b/mysql-test/t/func_str.test
@@ -125,3 +125,15 @@ CREATE TABLE t1 (id int(11) NOT NULL auto_increment, tmp text NOT NULL, KEY id (
 INSERT INTO t1 VALUES (1, 'a545f661efdd1fb66fdee3aab79945bf');
 SELECT 1 FROM t1 WHERE tmp=AES_DECRYPT(tmp,"password");
 DROP TABLE t1;
+
+CREATE TABLE t1 (
+  wid int(10) unsigned NOT NULL auto_increment,
+  data_podp date default NULL,
+  status_wnio enum('nowy','podp','real','arch') NOT NULL default 'nowy',
+  PRIMARY KEY(wid),
+);
+
+INSERT INTO t1 VALUES (8,NULL,'real');
+INSERT INTO t1 VALUES (9,NULL,'nowy');
+SELECT elt(status_wnio,data_podp) FROM t1 GROUP BY wid;
+DROP TABLE t1;