CREATE DATABASE IF NOT EXISTS `crashtest`;

USE `crashtest`;

drop table if exists t1;

CREATE TABLE `t1` (

  `id1`    INT(11)      NOT NULL AUTO_INCREMENT,

  `id2`    VARCHAR(30)  NOT NULL,

  `id3`    DATETIME     NOT NULL DEFAULT CURRENT_TIMESTAMP,

  PRIMARY KEY (`id1`),

  UNIQUE KEY `unique_id2` (`id2`)

);

ALTER TABLE `t1` CHANGE COLUMN `id2` `id4` VARCHAR(100) NOT NULL;

SELECT * FROM `t1` where id4 like 'a';

MariaDB [crashtest]> SELECT * FROM `t1` where id4 like 'a';

ERROR 2013 (HY000): Lost connection to MySQL server during query

CREATE DATABASE IF NOT EXISTS `crashtest`;

USE `crashtest`;

drop table if exists t1;

CREATE TABLE `t1` (

  `id1`    INT(11)      NOT NULL AUTO_INCREMENT,

  `id2`    VARCHAR(30)  NOT NULL,

  PRIMARY KEY (`id1`),

  UNIQUE KEY `unique_id2` (`id2`)

);

ALTER TABLE `t1` CHANGE COLUMN `id2` `id4` VARCHAR(100) NOT NULL;

SELECT * FROM `t1` where id4 like 'a';

2017-10-16 18:25:48 25472 [Note] C:\Program Files\MariaDB 10.2\bin\mysqld.exe: ready for connections.

Version: '10.2.9-MariaDB'  socket: ''  port: 3317  mariadb.org binary distribution

2017-10-16 18:25:48 35452 [Note] InnoDB: Buffer pool(s) load completed at 171016 18:25:48

2017-10-16 18:26:47 29244 [ERROR] Found index unique_id2 whose column info does not match that of MariaDB.

2017-10-16 18:26:47 29244 [ERROR] Build InnoDB index translation table for Table .\crashtest\t1 failed

171016 18:26:47 [ERROR] mysqld got exception 0xc0000005 ;

This could be because you hit a bug. It is also possible that this binary

or one of the libraries it was linked against is corrupt, improperly built,

or misconfigured. This error can also be caused by malfunctioning hardware.

To report this bug, see https://mariadb.com/kb/en/reporting-bugs

We will try our best to scrape up some info that will hopefully help

diagnose the problem, but since we have already crashed, 

something is definitely wrong and this may fail.

Server version: 10.2.9-MariaDB

key_buffer_size=134217728

read_buffer_size=131072

max_used_connections=1

max_threads=65537

thread_count=7

It is possible that mysqld could use up to 

key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 136039 K  bytes of memory

Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x11f13258

Attempting backtrace. You can use the following information to find out

where mysqld died. If you see no messages after this, something went

terribly wrong...

mysqld.exe!my_xml_error_string()

mysqld.exe!?get_tok_start_prev@Lex_input_stream@@QEAAPEBDXZ()

mysqld.exe!?ha_index_read_map@handler@@QEAAHPEAEPEBEKW4ha_rkey_function@@@Z()

mysqld.exe!?read_range_first@handler@@UEAAHPEBUst_key_range@@0_N1@Z()

mysqld.exe!?multi_range_read_next@handler@@UEAAHPEAPEAX@Z()

mysqld.exe!?get_next@Mrr_simple_index_reader@@UEAAHPEAPEAX@Z()

mysqld.exe!?dsmrr_next@DsMrr_impl@@QEAAHPEAPEAX@Z()

mysqld.exe!?get_next@QUICK_RANGE_SELECT@@UEAAHXZ()

mysqld.exe!?rr_from_pointers@@YAHPEAUREAD_RECORD@@@Z()

mysqld.exe!?sub_select@@YA?AW4enum_nested_loop_state@@PEAVJOIN@@PEAUst_join_table@@_N@Z()

mysqld.exe!?disjoin@?$List@VItem@@@@QEAAXPEAV1@@Z()

mysqld.exe!?exec_inner@JOIN@@QEAAXXZ()

mysqld.exe!?exec@JOIN@@QEAAXXZ()

mysqld.exe!?mysql_select@@YA_NPEAVTHD@@PEAUTABLE_LIST@@IAEAV?$List@VItem@@@@PEAVItem@@IPEAUst_order@@434_KPEAVselect_result@@PEAVst_select_lex_unit@@PEAVst_select_lex@@@Z()

mysqld.exe!?handle_select@@YA_NPEAVTHD@@PEAULEX@@PEAVselect_result@@K@Z()

mysqld.exe!?execute_init_command@@YAXPEAVTHD@@PEAUst_mysql_lex_string@@PEAUst_mysql_rwlock@@@Z()

mysqld.exe!?mysql_execute_command@@YAHPEAVTHD@@@Z()

mysqld.exe!?mysql_parse@@YAXPEAVTHD@@PEADIPEAVParser_state@@_N3@Z()

mysqld.exe!?dispatch_command@@YA_NW4enum_server_command@@PEAVTHD@@PEADI_N3@Z()

mysqld.exe!?do_command@@YA_NPEAVTHD@@@Z()

mysqld.exe!?pool_of_threads_scheduler@@YAXPEAUscheduler_functions@@PEAKPEAI@Z()

mysqld.exe!?tp_callback@@YAXPEAUTP_connection@@@Z()

ntdll.dll!TpPostWork()

ntdll.dll!TpDisassociateCallback()

kernel32.dll!BaseThreadInitThunk()

ntdll.dll!RtlUserThreadStart()

Trying to get some variables.

Some pointers may be invalid and cause the dump to abort.

Query (0x11f1fc40): SELECT * FROM `t1` where id4 like 'a'

Connection ID (thread ID): 9

Status: NOT_KILLED

Optimizer switch: index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on

The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains

information that should help you find out what is causing the crash.

2017-10-16 18:27:04 26064 [Note] InnoDB: page_cleaner: 1000ms intended loop took 5733ms. The settings might not be optimal. (flushed=0 and evicted=0, during the time.)