Merge mronstrom@bk-internal.mysql.com:/home/bk/mysql-4.1

into  c-4a09e253.1238-1-64736c10.cust.bredbandsbolaget.se:/home/pappa/bug12594

mysql-test/r/group_by.result

@@ -764,3 +764,12 @@ select date(left(f1+0,8)) from t1 group by 1;
 date(left(f1+0,8))
 2005-06-06
 drop table t1;
+create table t1(f1 varchar(5) key);
+insert into t1 values (1),(2);
+select sql_buffer_result max(f1) is null from t1;
+max(f1) is null
+0
+select sql_buffer_result max(f1)+1 from t1;
+max(f1)+1
+3
+drop table t1;

mysql-test/r/olap.result

@@ -516,3 +516,16 @@ a	b	c	count
 1	NULL	NULL	2
 NULL	NULL	NULL	2
 DROP TABLE t1;
+CREATE TABLE t1 (a int(11) NOT NULL);
+INSERT INTO t1 VALUES (1),(2);
+SELECT * FROM (SELECT a, a + 1, COUNT(*) FROM t1 GROUP BY a WITH ROLLUP) t;
+a	a + 1	COUNT(*)
+1	2	1
+2	3	1
+NULL	NULL	2
+SELECT * FROM (SELECT a, LENGTH(a), COUNT(*) FROM t1 GROUP BY a WITH ROLLUP) t;
+a	LENGTH(a)	COUNT(*)
+1	1	1
+2	1	1
+NULL	NULL	2
+DROP TABLE t1;

mysql-test/r/ps_1general.result

@@ -470,12 +470,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	14	N	1	31	8
+def					Extra	253	255	14	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	Using filesort
 SET @arg00=1 ;
@@ -486,12 +486,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	5	Y	0	31	8
-def					possible_keys	252	4096	7	Y	0	31	8
+def					possible_keys	253	4096	7	Y	0	31	8
 def					key	253	64	7	Y	0	31	8
 def					key_len	8	3	1	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	27	N	1	31	8
+def					Extra	253	255	27	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	range	PRIMARY	PRIMARY	4	NULL	3	Using where; Using filesort
 drop table if exists t2;

mysql-test/r/ps_2myisam.result

@@ -1153,12 +1153,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	0	N	1	31	8
+def					Extra	253	255	0	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t9	ALL	NULL	NULL	NULL	NULL	2	
 drop table if exists t2 ;

mysql-test/r/ps_3innodb.result

@@ -1153,12 +1153,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	0	N	1	31	8
+def					Extra	253	255	0	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t9	ALL	NULL	NULL	NULL	NULL	2	
 test_sequence

mysql-test/r/ps_4heap.result

@@ -1154,12 +1154,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	0	N	1	31	8
+def					Extra	253	255	0	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t9	ALL	NULL	NULL	NULL	NULL	2	
 test_sequence

mysql-test/r/ps_5merge.result

@@ -1196,12 +1196,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	0	N	1	31	8
+def					Extra	253	255	0	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t9	ALL	NULL	NULL	NULL	NULL	2	
 test_sequence
@@ -4210,12 +4210,12 @@ def					id	8	3	1	N	32929	0	63
 def					select_type	253	19	6	N	1	31	8
 def					table	253	64	2	Y	0	31	8
 def					type	253	10	3	Y	0	31	8
-def					possible_keys	252	4096	0	Y	0	31	8
+def					possible_keys	253	4096	0	Y	0	31	8
 def					key	253	64	0	Y	0	31	8
 def					key_len	8	3	0	Y	32928	0	63
-def					ref	252	1024	0	Y	0	31	8
+def					ref	253	1024	0	Y	0	31	8
 def					rows	8	10	1	Y	32928	0	63
-def					Extra	252	255	0	N	1	31	8
+def					Extra	253	255	0	N	1	31	8
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t9	ALL	NULL	NULL	NULL	NULL	2	
 test_sequence

mysql-test/t/group_by.test

@@ -600,4 +600,14 @@ insert into t1 values('2005-06-06');
 select date(left(f1+0,8)) from t1 group by 1;
 drop table t1;
 
+#
+# BUG#12695: Item_func_isnull::update_used_tables
+# did not update const_item_cache
+#
+create table t1(f1 varchar(5) key);
+insert into t1 values (1),(2);
+select sql_buffer_result max(f1) is null from t1;
+select sql_buffer_result max(f1)+1 from t1;
+drop table t1;
+
 # End of 4.1 tests

mysql-test/t/olap.test

@@ -250,4 +250,17 @@ SELECT a, b, a AS c, COUNT(*) AS count FROM t1 GROUP BY a, b, c WITH ROLLUP;
 
 DROP TABLE t1;
 
+#
+# Bug #11885:  derived table specified by a subquery with
+#              ROLLUP over expressions on not nullable group by attributes 
+#
+
+CREATE TABLE t1 (a int(11) NOT NULL);
+INSERT INTO t1 VALUES (1),(2);
+
+SELECT * FROM (SELECT a, a + 1, COUNT(*) FROM t1 GROUP BY a WITH ROLLUP) t;
+SELECT * FROM (SELECT a, LENGTH(a), COUNT(*) FROM t1 GROUP BY a WITH ROLLUP) t;
+
+DROP TABLE t1;
+
 # End of 4.1 tests

sql/item.cc

@@ -1973,14 +1973,7 @@ void Item::make_field(Send_field *tmp_field)
 
 void Item_empty_string::make_field(Send_field *tmp_field)
 {
-  enum_field_types type = FIELD_TYPE_VAR_STRING;  
-  if (max_length >= 16777216)    
-    type = FIELD_TYPE_LONG_BLOB;  
-  else if (max_length >= 65536)    
-    type = FIELD_TYPE_MEDIUM_BLOB;  
-  else if (max_length >= 256)    
-    type = FIELD_TYPE_BLOB;  
-  init_make_field(tmp_field, type);
+  init_make_field(tmp_field,FIELD_TYPE_VAR_STRING);
 }
 
 

sql/item_cmpfunc.h

@@ -826,7 +826,7 @@ class Item_func_isnull :public Item_bool_func
     else
     {
       args[0]->update_used_tables();
-      if (!(used_tables_cache=args[0]->used_tables()))
+      if ((const_item_cache= !(used_tables_cache= args[0]->used_tables())))
       {
 	/* Remember if the value is always NULL or never NULL */
 	cached_value= (longlong) args[0]->is_null();

sql/sql_select.cc

@@ -9277,6 +9277,8 @@ void free_underlaid_joins(THD *thd, SELECT_LEX *select)
     The function replaces occurrences of group by fields in expr
     by ref objects for these fields unless they are under aggregate
     functions.
+    The function also corrects value of the the maybe_null attribute
+    for the items of all subexpressions containing group by fields.
 
   IMPLEMENTATION
     The function recursively traverses the tree of the expr expression,
@@ -9287,6 +9289,9 @@ void free_underlaid_joins(THD *thd, SELECT_LEX *select)
     This substitution is needed GROUP BY queries with ROLLUP if
     SELECT list contains expressions over group by attributes.
 
+  TODO: Some functions are not null-preserving. For those functions
+    updating of the maybe_null attribute is an overkill. 
+
   EXAMPLES
     SELECT a+1 FROM t1 GROUP BY a WITH ROLLUP
     SELECT SUM(a)+a FROM t1 GROUP BY a WITH ROLLUP 
@@ -9307,6 +9312,7 @@ static bool change_group_ref(THD *thd, Item_func *expr, ORDER *group_list,
          arg != arg_end; arg++)
     {
       Item *item= *arg;
+      bool arg_changed= FALSE;
       if (item->type() == Item::FIELD_ITEM || item->type() == Item::REF_ITEM)
       {
         ORDER *group_tmp;
@@ -9318,15 +9324,20 @@ static bool change_group_ref(THD *thd, Item_func *expr, ORDER *group_list,
             if(!(new_item= new Item_ref(group_tmp->item, 0, item->name)))
               return 1;                                 // fatal_error is set
             thd->change_item_tree(arg, new_item);
-            *changed= TRUE;
+            arg_changed= TRUE;
           }
         }
       }
       else if (item->type() == Item::FUNC_ITEM)
       {
-        if (change_group_ref(thd, (Item_func *) item, group_list, changed))
+        if (change_group_ref(thd, (Item_func *) item, group_list, &arg_changed))
           return 1;
       }
+      if (arg_changed)
+      {
+        expr->maybe_null= 1;
+        *changed= TRUE;
+      }
     }
   }
   return 0;
@@ -9389,7 +9400,7 @@ bool JOIN::rollup_init()
     }
     if (item->type() == Item::FUNC_ITEM)
     {
-      bool changed= 0;
+      bool changed= FALSE;
       if (change_group_ref(thd, (Item_func *) item, group_list, &changed))
         return 1;
       /*

sql/sql_show.cc

@@ -638,33 +638,6 @@ int mysqld_extend_show_tables(THD *thd,const char *db,const char *wild)
   DBUG_RETURN(0);
 }
 
-/*
-   returns the length of the longest type on the given table.
-
-   This is used so that show fields will return the data using the proper 
-   lengths instead of forcing columns such as type to always return with a 
-   given length.
-*/
-
-uint get_longest_type_in_table(TABLE *table, const char *wild)
-{  
-  Field **ptr,*field;
-  char tmp[MAX_FIELD_WIDTH];
-  uint max_len= 0;
-
-  for (ptr=table->field; (field= *ptr); ptr++)
-  {
-    if (!wild || !wild[0] ||
-        !wild_case_compare(system_charset_info, field->field_name,wild))
-    {
-      String type(tmp,sizeof(tmp), system_charset_info);
-      field->sql_type(type);
-      max_len= max(max_len, type.length());
-    }
-  }
-  return max_len;
-}
-
 
 /***************************************************************************
 ** List all columns in a table_list->real_name
@@ -694,14 +667,9 @@ mysqld_show_fields(THD *thd, TABLE_LIST *table_list,const char *wild,
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   (void) get_table_grant(thd, table_list);
 #endif
-
-  /* we scan for the longest since long enum types can exceed 40 */
-  uint max_len = get_longest_type_in_table(table, wild);
-
   List<Item> field_list;
   field_list.push_back(new Item_empty_string("Field",NAME_LEN));
-  field_list.push_back(new Item_empty_string("Type",
-	max_len > 40 ? max_len : 40));
+  field_list.push_back(new Item_empty_string("Type", 40));
   if (verbose)
     field_list.push_back(new Item_empty_string("Collation",40));
   field_list.push_back(new Item_empty_string("Null",1));

tests/mysql_client_test.c

@@ -7182,7 +7182,7 @@ static void test_explain_bug()
   verify_prepare_field(result, 3, "type", "", MYSQL_TYPE_VAR_STRING,
                        "", "", "", 10, 0);
 
-  verify_prepare_field(result, 4, "possible_keys", "", MYSQL_TYPE_BLOB,
+  verify_prepare_field(result, 4, "possible_keys", "", MYSQL_TYPE_VAR_STRING,
                        "", "", "", NAME_LEN*64, 0);
 
   verify_prepare_field(result, 5, "key", "", MYSQL_TYPE_VAR_STRING,
@@ -7195,13 +7195,13 @@ static void test_explain_bug()
                        (mysql_get_server_version(mysql) <= 50000 ? 3 : 4096),
                        0);
 
-  verify_prepare_field(result, 7, "ref", "", MYSQL_TYPE_BLOB,
+  verify_prepare_field(result, 7, "ref", "", MYSQL_TYPE_VAR_STRING,
                        "", "", "", NAME_LEN*16, 0);
 
   verify_prepare_field(result, 8, "rows", "", MYSQL_TYPE_LONGLONG,
                        "", "", "", 10, 0);
 
-  verify_prepare_field(result, 9, "Extra", "", MYSQL_TYPE_BLOB,
+  verify_prepare_field(result, 9, "Extra", "", MYSQL_TYPE_VAR_STRING,
                        "", "", "", 255, 0);
 
   mysql_free_result(result);