MDEV-4281 Assertion `maybe_null && item->null_value' fails in make_sortkey on...

MDEV-4281 Assertion `maybe_null && item->null_value' fails in make_sortkey on CASE with different return types, GROUP_CONCAT, GROUP BY

Fix Item::get_date() to mark the item NULL when returning an error.

mysql-test/r/cast.result

@@ -268,37 +268,37 @@ cast(010203101112.121314 as datetime)
 0001-02-03 10:11:12
 select cast(120010203101112.121314 as datetime);
 cast(120010203101112.121314 as datetime)
-NULL
+0000-00-00 00:00:00
 Warnings:
 Warning	1292	Incorrect datetime value: '120010203101112.121314'
 select cast(cast(1.1 as decimal) as datetime);
 cast(cast(1.1 as decimal) as datetime)
-NULL
+0000-00-00 00:00:00
 Warnings:
 Warning	1292	Incorrect datetime value: '1'
 select cast(cast(-1.1 as decimal) as datetime);
 cast(cast(-1.1 as decimal) as datetime)
-NULL
+0000-00-00 00:00:00
 Warnings:
 Warning	1292	Incorrect datetime value: '-1'
 select cast('0' as date);
 cast('0' as date)
-NULL
+0000-00-00
 Warnings:
 Warning	1292	Incorrect datetime value: '0'
 select cast('' as date);
 cast('' as date)
-NULL
+0000-00-00
 Warnings:
 Warning	1292	Incorrect datetime value: ''
 select cast('0' as datetime);
 cast('0' as datetime)
-NULL
+0000-00-00 00:00:00
 Warnings:
 Warning	1292	Incorrect datetime value: '0'
 select cast('' as datetime);
 cast('' as datetime)
-NULL
+0000-00-00 00:00:00
 Warnings:
 Warning	1292	Incorrect datetime value: ''
 select cast('0' as time);
@@ -306,7 +306,7 @@ cast('0' as time)
 00:00:00
 select cast('' as time);
 cast('' as time)
-NULL
+00:00:00
 Warnings:
 Warning	1292	Truncated incorrect time value: ''
 select cast(NULL as DATE);
@@ -323,13 +323,13 @@ cast(NULL as BINARY)
 NULL
 select cast(cast(120010203101112.121314 as double) as datetime);
 cast(cast(120010203101112.121314 as double) as datetime)
-NULL
+0000-00-00 00:00:00
 select cast(cast(1.1 as double) as datetime);
 cast(cast(1.1 as double) as datetime)
 0000-00-00 00:00:01
 select cast(cast(-1.1 as double) as datetime);
 cast(cast(-1.1 as double) as datetime)
-NULL
+0000-00-00 00:00:00
 explain extended select cast(10 as double(5,2));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used

mysql-test/r/date_formats.result

@@ -586,7 +586,7 @@ TIME_FORMAT("25:00:00", '%l %p')
 1 AM
 SELECT DATE_FORMAT('%Y-%m-%d %H:%i:%s', 1151414896);
 DATE_FORMAT('%Y-%m-%d %H:%i:%s', 1151414896)
-NULL
+1151414896
 Warnings:
 Warning	1292	Incorrect datetime value: '%Y-%m-%d %H:%i:%s'
 select str_to_date('04 /30/2004', '%m /%d/%Y');

mysql-test/r/func_sapdb.result

@@ -168,7 +168,7 @@ date("1997-12-31 23:59:59.000001")
 1997-12-31
 select date("1997-13-31 23:59:59.000001");
 date("1997-13-31 23:59:59.000001")
-NULL
+0000-00-00
 Warnings:
 Warning	1292	Incorrect datetime value: '1997-13-31 23:59:59.000001'
 select time("1997-12-31 23:59:59.000001");
@@ -176,7 +176,7 @@ time("1997-12-31 23:59:59.000001")
 23:59:59.000001
 select time("1997-12-31 25:59:59.000001");
 time("1997-12-31 25:59:59.000001")
-NULL
+00:00:00
 Warnings:
 Warning	1292	Truncated incorrect time value: '1997-12-31 25:59:59.000001'
 select microsecond("1997-12-31 23:59:59.000001");

mysql-test/r/func_time.result

@@ -946,7 +946,6 @@ select f1 from t1 where cast("2006-1-1" as date) between f1 and cast('zzz' as da
 f1
 Warnings:
 Warning	1292	Incorrect datetime value: 'zzz'
-Warning	1292	Incorrect datetime value: 'zzz'
 select f1 from t1 where makedate(2006,1) between date(f1) and date(f3);
 f1
 2006-01-01
@@ -1756,7 +1755,7 @@ Warnings:
 Warning	1441	Datetime function: time field overflow
 select cast('131415.123e0' as time);
 cast('131415.123e0' as time)
-NULL
+00:00:00
 Warnings:
 Warning	1292	Truncated incorrect time value: '131415.123e0'
 select cast('2010-01-02 03:04:05' as datetime) between null and '2010-01-02 03:04:04';
@@ -1776,12 +1775,12 @@ unix_timestamp(null)
 NULL
 select truncate(date('2010-40-10'), 6);
 truncate(date('2010-40-10'), 6)
-NULL
+0.000000
 Warnings:
 Warning	1292	Incorrect datetime value: '2010-40-10'
 select extract(month from '2010-40-50');
 extract(month from '2010-40-50')
-NULL
+0
 Warnings:
 Warning	1292	Incorrect datetime value: '2010-40-50'
 select subtime('0000-00-10 10:10:10', '30 10:00:00');

mysql-test/r/partition_pruning.result

@@ -1906,9 +1906,10 @@ INSERT INTO t1 VALUES (1, '2009-01-01'), (2, NULL);
 # test with an invalid date, which lead to item->null_value is set.
 EXPLAIN PARTITIONS SELECT * FROM t1 WHERE b < CAST('2009-04-99' AS DATETIME);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+1	SIMPLE	t1	p20090401	ALL	NULL	NULL	NULL	NULL	2	Using where
 Warnings:
 Warning	1292	Incorrect datetime value: '2009-04-99'
+Warning	1292	Incorrect datetime value: '2009-04-99'
 DROP TABLE t1;
 CREATE TABLE t1
 (a INT NOT NULL AUTO_INCREMENT,

mysql-test/r/type_date.result

@@ -136,7 +136,7 @@ select @d:=1311;
 1311
 select year(@d), month(@d), day(@d), cast(@d as date);
 year(@d)	month(@d)	day(@d)	cast(@d as date)
-NULL	NULL	NULL	NULL
+0	0	0	0000-00-00
 Warnings:
 Warning	1292	Incorrect datetime value: '1311'
 Warning	1292	Incorrect datetime value: '1311'

mysql-test/r/type_datetime.result

@@ -573,7 +573,7 @@ CAST('NULL' AS DATE) < CAST('2008-01-01' AS DATE) n7,
 CAST('2008-01-01' AS DATE) < CAST('NULL' AS DATE) n8,
 CAST('NULL' AS DATE) < CAST('NULL' AS DATE) n9;
 n1	n2	n3	n4	n5	n6	n7	n8	n9
-0	0	1	NULL	NULL	NULL	NULL	NULL	NULL
+0	0	1	1	1	0	1	0	0
 Warnings:
 Warning	1292	Incorrect datetime value: 'NULL'
 Warning	1292	Incorrect datetime value: 'NULL'
@@ -585,6 +585,8 @@ Warning	1292	Incorrect datetime value: 'NULL'
 Warning	1292	Incorrect datetime value: 'NULL'
 Warning	1292	Incorrect datetime value: 'NULL'
 Warning	1292	Incorrect datetime value: 'NULL'
+Warning	1292	Incorrect datetime value: 'NULL'
+Warning	1292	Incorrect datetime value: 'NULL'
 End of 5.0 tests
 set @org_mode=@@sql_mode;
 create table t1 (da date default '1962-03-03 23:33:34', dt datetime default '1962-03-03');
@@ -651,3 +653,16 @@ SELECT * FROM t1;
 dt1
 DROP TABLE t1;
 End of 5.1 tests
+create table t1 (d date, t time) engine=myisam;
+insert into t1 values ('2000-12-03','22:55:23'),('2008-05-03','10:19:31');
+select case when d = '2012-12-12' then d else t end as cond, group_concat( d ) from t1 group by cond;
+cond	group_concat( d )
+0000-00-00 00:00:00	2000-12-03
+0000-00-00 00:00:00	2008-05-03
+Warnings:
+Warning	1292	Incorrect datetime value: '22:55:23'
+Warning	1292	Incorrect datetime value: '10:19:31'
+Warning	1292	Incorrect datetime value: '22:55:23'
+Warning	1292	Incorrect datetime value: '10:19:31'
+drop table t1;
+End of 5.3 tests

mysql-test/t/type_datetime.test

@@ -462,3 +462,14 @@ SELECT * FROM t1;
 DROP TABLE t1;
 
 --echo End of 5.1 tests
+
+#
+# MDEV-4281 Assertion `maybe_null && item->null_value' fails in make_sortkey on CASE with different return types, GROUP_CONCAT, GROUP BY
+#
+create table t1 (d date, t time) engine=myisam;
+insert into t1 values ('2000-12-03','22:55:23'),('2008-05-03','10:19:31');
+select case when d = '2012-12-12' then d else t end as cond, group_concat( d ) from t1 group by cond;
+drop table t1;
+
+--echo End of 5.3 tests
+

sql/filesort.cc

@@ -869,7 +869,10 @@ static void make_sortkey(register SORTPARAM *param,
           {
             MYSQL_TIME buf;
             if (item->get_date_result(&buf, TIME_FUZZY_DATE | TIME_INVALID_DATES))
-              DBUG_ASSERT(maybe_null && item->null_value);
+            {
+              DBUG_ASSERT(maybe_null);
+              DBUG_ASSERT(item->null_value);
+            }
             else
               value= pack_time(&buf);
           }

sql/item.cc

@@ -1197,11 +1197,15 @@ bool Item::get_date(MYSQL_TIME *ltime,uint fuzzydate)
     DBUG_ASSERT(0);
   }
 
-  return 0;
+  return null_value= 0;
 
 err:
+  /*
+    if the item was not null and convertion failed, we return a zero date
+    if allowed, otherwise - null.
+  */
   bzero((char*) ltime,sizeof(*ltime));
-  return 1;
+  return null_value|= (fuzzydate & (TIME_NO_ZERO_DATE|TIME_NO_ZERO_IN_DATE));
 }
 
 bool Item::get_seconds(ulonglong *sec, ulong *sec_part)