From dccac5839636906822aa4e07fb7da79fb2668ab6 Mon Sep 17 00:00:00 2001
From: unknown <serg@serg.mysql.com>
Date: Tue, 11 Mar 2003 21:20:53 +0100
Subject: [PATCH] fixed an obscure bug in group by + having +
 Item_ref::get_date

---
 mysql-test/r/group_by.result |  1 +
 mysql-test/t/group_by.test   |  8 ++++++++
 sql/item.cc                  | 11 +++++++++++
 sql/item.h                   | 11 +++++++----
 4 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/mysql-test/r/group_by.result b/mysql-test/r/group_by.result
index 113f8325685..0073827056d 100644
--- a/mysql-test/r/group_by.result
+++ b/mysql-test/r/group_by.result
@@ -128,3 +128,4 @@ a	MAX(b)	ELT(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f')
 a	MAX(b)	MAKE_SET(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h')
 1	4	c
 10	43	a,b,d,f
+a	c	count(distinct rand())
diff --git a/mysql-test/t/group_by.test b/mysql-test/t/group_by.test
index 6e256d7896f..20e11713d31 100644
--- a/mysql-test/t/group_by.test
+++ b/mysql-test/t/group_by.test
@@ -346,3 +346,11 @@ select a, MAX(b), CONCAT_WS(MAX(b), '43', '4', '5') from t1 group by a;
 select a, MAX(b), ELT(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f') from t1 group by a;
 select a, MAX(b), MAKE_SET(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h') from t1 group by a;
 drop table t1;
+
+# not purely group_by bug, but group_by is involved...
+
+create table t1 (a date default null, b date default null);
+insert t1 values ('1999-10-01','2000-01-10'), ('1997-01-01','1998-10-01');
+select a,min(b) c,count(distinct rand()) from t1 group by a having c<a + interval 1 day;
+drop table t1;
+
diff --git a/sql/item.cc b/sql/item.cc
index 9b4274ab71d..a2d9f0b2575 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -194,6 +194,17 @@ bool Item_field::get_date(TIME *ltime,bool fuzzydate)
   return 0;
 }
 
+bool Item_field::get_date_result(TIME *ltime,bool fuzzydate)
+{
+  if ((null_value=result_field->is_null()) ||
+      result_field->get_date(ltime,fuzzydate))
+  {
+    bzero((char*) ltime,sizeof(*ltime));
+    return 1;
+  }
+  return 0;
+}
+
 bool Item_field::get_time(TIME *ltime)
 {
   if ((null_value=field->is_null()) || field->get_time(ltime))
diff --git a/sql/item.h b/sql/item.h
index 408010d211a..3cf5a17805c 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -82,6 +82,8 @@ public:
   virtual void split_sum_func(List<Item> &fields) {}
   virtual bool get_date(TIME *ltime,bool fuzzydate);
   virtual bool get_time(TIME *ltime);
+  virtual bool get_date_result(TIME *ltime,bool fuzzydate)
+  { return get_date(ltime,fuzzydate); }
 };
 
 
@@ -129,8 +131,9 @@ public:
     return field->result_type();
   }
   Field *tmp_table_field() { return result_field; }
-  bool get_date(TIME *ltime,bool fuzzydate);  
-  bool get_time(TIME *ltime);  
+  bool get_date(TIME *ltime,bool fuzzydate);
+  bool get_date_result(TIME *ltime,bool fuzzydate);
+  bool get_time(TIME *ltime);
 };
 
 
@@ -332,8 +335,8 @@ public:
     return tmp;
   }
   bool get_date(TIME *ltime,bool fuzzydate)
-  {  
-    return (null_value=(*ref)->get_date(ltime,fuzzydate));
+  {
+    return (null_value=(*ref)->get_date_result(ltime,fuzzydate));
   }
   bool send(String *tmp)		{ return (*ref)->send(tmp); }
   void make_field(Send_field *field)	{ (*ref)->make_field(field); }