| Bug #70014 | MySQL crashes on explain with JSON formatting (debug builds) | ||
|---|---|---|---|
| Submitted: | 13 Aug 2013 13:34 | Modified: | 19 Nov 2013 16:31 |
| Reporter: | Bjorn Seime | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Optimizer | Severity: | S2 (Serious) |
| Version: | 5.6.12-debug, 5.6.13-debug , 5.7.2-m12-enterprise-commercial-advanced-debug | OS: | Linux (Fedora 18) |
| Assigned to: | CPU Architecture: | Any | |
| Tags: | debug-build, explain, json | ||
[13 Aug 2013 13:43]
Bjorn Seime
Stack trace from MySQL 5.7.2-m12-debug-log
Attachment: mysqld.1.err (application/octet-stream, text), 6.18 KiB.
[13 Aug 2013 13:45]
Bjorn Seime
The crash was also present in version 5.7.2-m12-debug-log. See attached error log for stack trace.
[13 Aug 2013 14:13]
MySQL Verification Team
Hello Bjorn, Thank you for the bug report and the test case. Verified as described on debug builds of 5.6.13-debug , 5.7.2-m12-debug-log. Thanks, Umesh
[15 Aug 2013 13:17]
MySQL Verification Team
Adding this comment for search engines to pick up: Version: '5.7.2-m12-debug' socket: '' port: 3306 MySQL Community Server (GPL) Assertion failed: !"No derived table found!", file opt_explain_json.cc, line 1941 mysqld-debug.exe!my_sigabrt_handler()[my_thr_init.c:451] mysqld-debug.exe!raise()[winsig.c:593] mysqld-debug.exe!abort()[abort.c:81] mysqld-debug.exe!_wassert()[assert.c:153] mysqld-debug.exe!Explain_format_JSON::end_context()[opt_explain_json.cc:1941] mysqld-debug.exe!Explain::explain_subqueries()[opt_explain.cc:635] mysqld-debug.exe!Explain::send()[opt_explain.cc:683] mysqld-debug.exe!explain_query_specification()[opt_explain.cc:2025] mysqld-debug.exe!mysql_explain_unit()[opt_explain.cc:2154] mysqld-debug.exe!explain_query()[opt_explain.cc:2094] mysqld-debug.exe!execute_sqlcom_select()[sql_parse.cc:4872] mysqld-debug.exe!mysql_execute_command()[sql_parse.cc:2495] mysqld-debug.exe!mysql_parse()[sql_parse.cc:5274] mysqld-debug.exe!dispatch_command()[sql_parse.cc:1331] mysqld-debug.exe!do_command()[sql_parse.cc:1027] mysqld-debug.exe!handle_connection()[connection_handler_per_thread.cc:227] mysqld-debug.exe!pfs_spawn_thread()[pfs.cc:1985] mysqld-debug.exe!pthread_start()[my_winthread.c:60] mysqld-debug.exe!_callthreadstartex()[threadex.c:314] mysqld-debug.exe!_threadstartex()[threadex.c:297]
[19 Nov 2013 16:31]
Paul DuBois
Noted in 5.7.4 changelog. For debug builds, JSON-format EXPLAIN statements for queries that involve semi-join materialization could cause a server exit.
Description: MySQL crashes when executing the following query: explain format=JSON select * from ( select d from item where d in ( select d from item where c in ('Freeeze'))) crash_query; How to repeat: create database json_explain_bug; use json_explain_bug; create table item ( id int, d int, c char(10) ); insert into item values (1, 2, 'a'), (2, 3, 'b'), (3, 3, 'c'); create index i_id on item(id); create index i_d on item(d); create index i_c on item(c); explain format=JSON select * from ( select d from item where d in ( select d from item where c in ('Freeeze'))) crash_query;