[MDEV-18881] Assertion `0' failed in make_sortkey upon SELECT with GROUP BY after LOAD DATA Created: 2019-03-11  Updated: 2019-03-18  Resolved: 2019-03-18

Status: Closed
Project: MariaDB Server
Component/s: Data types, Server
Affects Version/s: 5.5, 10.0, 10.1, 10.2, 10.3, 10.4
Fix Version/s: 10.2.23, 10.1.39, 10.3.14, 10.4.4

Type: Bug Priority: Major
Reporter: Elena Stepanova Assignee: Alexander Barkov
Resolution: Fixed Votes: 0
Labels: None


 Description    

CREATE TABLE t1 (a BIT(22), b CHAR(8) NOT NULL, c CHAR(8));
 
INSERT INTO t1 VALUES (b'101001001011','foo','qux'),(b'100011110101','bar','foobar');
 
 
 
SELECT * FROM t1 INTO OUTFILE 'load_t1';
 
LOAD DATA INFILE 'load_t1' IGNORE INTO TABLE t1;
 
SET SESSION SQL_MODE= '';
 
SELECT GROUP_CONCAT(c) AS f FROM t1 GROUP BY LPAD('foo', 20, b);
 
 
 
# Cleanup
 
--let $datadir= `SELECT @@datadir`
 
--remove_file $datadir/test/load_t1
 
DROP TABLE t1;

10.1 6567636b

 
mysqld: /data/src/10.1/sql/filesort.cc:1016: void make_sortkey(Sort_param*, uchar*, uchar*): Assertion `0' failed.
 
190311 16:55:15 [ERROR] mysqld got signal 6 ;
 
 
 
#7  0x00007fb813227ee2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6
 
#8  0x0000560be35f94c2 in make_sortkey (param=0x7fb8152a9aa0, to=0x7fb80a45b4b6 '\245' <repeats 200 times>..., ref_pos=0x7fb8152a98b0 "") at /data/src/10.1/sql/filesort.cc:1016
 
#9  0x0000560be35f8d9f in find_all_keys (thd=0x7fb80c0d5070, param=0x7fb8152a9aa0, select=0x7fb80a445840, fs_info=0x7fb8152a9a30, buffpek_pointers=0x7fb8152a9ca0, tempfile=0x7fb8152a9b20, pq=0x0, found_rows=0x7fb8152a9ea8) at /data/src/10.1/sql/filesort.cc:840
 
#10 0x0000560be35f7469 in filesort (thd=0x7fb80c0d5070, table=0x7fb80a481c70, sortorder=0x7fb80a446810, s_length=1, select=0x7fb80a445840, max_rows=18446744073709551615, sort_positions=false, examined_rows=0x7fb8152a9ea0, found_rows=0x7fb8152a9ea8, tracker=0x7fb80a446850) at /data/src/10.1/sql/filesort.cc:301
 
#11 0x0000560be342ef07 in create_sort_index (thd=0x7fb80c0d5070, join=0x7fb80a444268, order=0x7fb80a444130, filesort_limit=18446744073709551615, select_limit=18446744073709551615, is_order_by=false) at /data/src/10.1/sql/sql_select.cc:21677
 
#12 0x0000560be34014a0 in JOIN::exec_inner (this=0x7fb80a444268) at /data/src/10.1/sql/sql_select.cc:3245
 
#13 0x0000560be33fe949 in JOIN::exec (this=0x7fb80a444268) at /data/src/10.1/sql/sql_select.cc:2562
 
#14 0x0000560be3401edf in mysql_select (thd=0x7fb80c0d5070, rref_pointer_array=0x7fb80c0d9560, tables=0x7fb80a443770, wild_num=0, fields=..., conds=0x0, og_num=1, order=0x0, group=0x7fb80a444130, having=0x0, proc_param=0x0, select_options=2147748608, result=0x7fb80a444248, unit=0x7fb80c0d8bb8, select_lex=0x7fb80c0d92b8) at /data/src/10.1/sql/sql_select.cc:3499
 
#15 0x0000560be33f7598 in handle_select (thd=0x7fb80c0d5070, lex=0x7fb80c0d8af0, result=0x7fb80a444248, setup_tables_done_option=0) at /data/src/10.1/sql/sql_select.cc:388
 
#16 0x0000560be33c6f2e in execute_sqlcom_select (thd=0x7fb80c0d5070, all_tables=0x7fb80a443770) at /data/src/10.1/sql/sql_parse.cc:5991
 
#17 0x0000560be33bd335 in mysql_execute_command (thd=0x7fb80c0d5070) at /data/src/10.1/sql/sql_parse.cc:3042
 
#18 0x0000560be33cab71 in mysql_parse (thd=0x7fb80c0d5070, rawbuf=0x7fb80a443088 "SELECT GROUP_CONCAT(c) AS f FROM t1 GROUP BY LPAD('foo', 20, b)", length=63, parser_state=0x7fb8152ab1e0) at /data/src/10.1/sql/sql_parse.cc:7509
 
#19 0x0000560be33b9320 in dispatch_command (command=COM_QUERY, thd=0x7fb80c0d5070, packet=0x7fb80ebf9071 "SELECT GROUP_CONCAT(c) AS f FROM t1 GROUP BY LPAD('foo', 20, b)", packet_length=63) at /data/src/10.1/sql/sql_parse.cc:1496
 
#20 0x0000560be33b80ab in do_command (thd=0x7fb80c0d5070) at /data/src/10.1/sql/sql_parse.cc:1124
 
#21 0x0000560be34f328e in do_handle_one_connection (thd_arg=0x7fb80c0d5070) at /data/src/10.1/sql/sql_connect.cc:1330
 
#22 0x0000560be34f2ff2 in handle_one_connection (arg=0x7fb80c0d5070) at /data/src/10.1/sql/sql_connect.cc:1242
 
#23 0x0000560be38b1ab4 in pfs_spawn_thread (arg=0x7fb812839ef0) at /data/src/10.1/storage/perfschema/pfs.cc:1861
 
#24 0x00007fb814f2b494 in start_thread (arg=0x7fb8152ac700) at pthread_create.c:333
 
#25 0x00007fb8132e493f in clone () from /lib/x86_64-linux-gnu/libc.so.6

10.4 5a796f1f

 
mysqld: /data/src/10.4/sql/filesort.cc:990: virtual void Type_handler_string_result::make_sort_key(uchar*, Item*, const SORT_FIELD_ATTR*, Sort_param*) const: Assertion `0' failed.
 
190311 16:59:25 [ERROR] mysqld got signal 6 ;
 
 
 
#7  0x00007f62cfefbee2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6
 
#8  0x0000564111d0b859 in Type_handler_string_result::make_sort_key (this=0x56411306e4f8 <type_handler_varchar>, to=0x7f62b806b2a6 '\245' <repeats 200 times>..., item=0x7f62b80169c8, sort_field=0x7f62b8019cb8, param=0x7f62ca073900) at /data/src/10.4/sql/filesort.cc:990
 
#9  0x0000564111d0c235 in make_sortkey (param=0x7f62ca073900, to=0x7f62b806b2a6 '\245' <repeats 200 times>..., ref_pos=0x7f62b813c650 "") at /data/src/10.4/sql/filesort.cc:1184
 
#10 0x0000564111d0b128 in find_all_keys (thd=0x7f62b8000b00, param=0x7f62ca073900, select=0x7f62b80190c8, fs_info=0x7f62b806aea0, buffpek_pointers=0x7f62ca073b00, tempfile=0x7f62ca073990, pq=0x0, found_rows=0x7f62b806b080) at /data/src/10.4/sql/filesort.cc:832
 
#11 0x0000564111d09416 in filesort (thd=0x7f62b8000b00, table=0x7f62b813b4a0, filesort=0x7f62b8019580, tracker=0x7f62b8019c38, join=0x7f62b8017428, first_table_bit=1) at /data/src/10.4/sql/filesort.cc:272
 
#12 0x0000564111a508d3 in create_sort_index (thd=0x7f62b8000b00, join=0x7f62b8017428, tab=0x7f62b8018748, fsort=0x7f62b8019580) at /data/src/10.4/sql/sql_select.cc:23191
 
#13 0x0000564111a4afea in st_join_table::sort_table (this=0x7f62b8018748) at /data/src/10.4/sql/sql_select.cc:20998
 
#14 0x0000564111a4abf1 in join_init_read_record (tab=0x7f62b8018748) at /data/src/10.4/sql/sql_select.cc:20935
 
#15 0x0000564111a48a7b in sub_select (join=0x7f62b8017428, join_tab=0x7f62b8018748, end_of_records=false) at /data/src/10.4/sql/sql_select.cc:20015
 
#16 0x0000564111a4800b in do_select (join=0x7f62b8017428, procedure=0x0) at /data/src/10.4/sql/sql_select.cc:19556
 
#17 0x0000564111a1eac7 in JOIN::exec_inner (this=0x7f62b8017428) at /data/src/10.4/sql/sql_select.cc:4371
 
#18 0x0000564111a1dc6e in JOIN::exec (this=0x7f62b8017428) at /data/src/10.4/sql/sql_select.cc:4153
 
#19 0x0000564111a1f320 in mysql_select (thd=0x7f62b8000b00, tables=0x7f62b8016050, wild_num=0, fields=..., conds=0x0, og_num=1, order=0x0, group=0x7f62b8016ae0, having=0x0, proc_param=0x0, select_options=2147748608, result=0x7f62b8017400, unit=0x7f62b8004a28, select_lex=0x7f62b80155a8) at /data/src/10.4/sql/sql_select.cc:4585
 
#20 0x0000564111a0f898 in handle_select (thd=0x7f62b8000b00, lex=0x7f62b8004960, result=0x7f62b8017400, setup_tables_done_option=0) at /data/src/10.4/sql/sql_select.cc:424
 
#21 0x00005641119d8c23 in execute_sqlcom_select (thd=0x7f62b8000b00, all_tables=0x7f62b8016050) at /data/src/10.4/sql/sql_parse.cc:6651
 
#22 0x00005641119cdede in mysql_execute_command (thd=0x7f62b8000b00) at /data/src/10.4/sql/sql_parse.cc:3888
 
#23 0x00005641119dcb63 in mysql_parse (thd=0x7f62b8000b00, rawbuf=0x7f62b80154c8 "SELECT GROUP_CONCAT(c) AS f FROM t1 GROUP BY LPAD('foo', 20, b)", length=63, parser_state=0x7f62ca075180, is_com_multi=false, is_next_command=false) at /data/src/10.4/sql/sql_parse.cc:8204
 
#24 0x00005641119c81a5 in dispatch_command (command=COM_QUERY, thd=0x7f62b8000b00, packet=0x7f62b800a781 "", packet_length=63, is_com_multi=false, is_next_command=false) at /data/src/10.4/sql/sql_parse.cc:1829
 
#25 0x00005641119c698b in do_command (thd=0x7f62b8000b00) at /data/src/10.4/sql/sql_parse.cc:1358
 
#26 0x0000564111b40703 in do_handle_one_connection (connect=0x5641142c1340) at /data/src/10.4/sql/sql_connect.cc:1399
 
#27 0x0000564111b40474 in handle_one_connection (arg=0x5641142c1340) at /data/src/10.4/sql/sql_connect.cc:1302
 
#28 0x0000564112036031 in pfs_spawn_thread (arg=0x5641143b39b0) at /data/src/10.4/storage/perfschema/pfs.cc:1862
 
#29 0x00007f62d1bd2494 in start_thread (arg=0x7f62ca076700) at pthread_create.c:333
 
#30 0x00007f62cffb893f in clone () from /lib/x86_64-linux-gnu/libc.so.6

No crash on a non-debug build.

 Comments   
Comment by Alexander Barkov [ 2019-03-12 ]

Repeatable with this SQL script:

DROP TABLE IF EXISTS t1;
 
CREATE TABLE t1 (a BIT(22), b CHAR(8) NOT NULL, c CHAR(8));
 
 
 
INSERT INTO t1 VALUES (0xA4B,'foo','qux');
 
INSERT INTO t1 VALUES (0x8F5,'bar','foobar');
 
INSERT INTO t1 VALUES (0x0, '', NULL);
 
INSERT INTO t1 VALUES (0x4B, 'foo','qux');
 
INSERT INTO t1 VALUES (0x8F5, 'bar', 'foobar');
 
 
 
SET SESSION SQL_MODE= '';
 
SELECT GROUP_CONCAT(c) AS f FROM t1 GROUP BY LPAD('foo', 20, b);

Comment by Alexander Barkov [ 2019-03-12 ]

The problem happens because during the preparation step (fix_fields), LPAD() determines its result as NOT NULL, however, val_str() later returns a NULL result.
This script demonstrates this inconsistency:

DROP TABLE IF EXISTS t1;
 
CREATE TABLE t1 AS SELECT LPAD('foo',20,'');
 
SHOW WARNINGS;
 
SELECT * FROM t1;


+---------+------+-------------------------------------------+
 
| Level   | Code | Message                                   |
 
+---------+------+-------------------------------------------+
 
| Warning | 1048 | Column 'LPAD('foo',20,'')' cannot be null |
 
+---------+------+-------------------------------------------+


+-------------------+
 
| LPAD('foo',20,'') |
 
+-------------------+
 
|                   |
 
+-------------------+

Notice:

  • the column was created as NOT NULL
  • the value was evaluated as NULL
  • the column converted NULL to an empty string on insertion
Generated at Thu Feb 08 08:47:26 UTC 2024 using Jira 8.20.16#820016-sha1:9d11dbea5f4be3d4cc21f03a88dd11d8c8687422.