190827 23:09:08 [ERROR] mysqld got signal 11 ; 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: 10.3.17-MariaDB-1:10.3.17+maria~bionic key_buffer_size=134217728 read_buffer_size=2097152 max_used_connections=1 max_threads=102 thread_count=7 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 760034 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. Thread pointer: 0x7f1370000c08 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... stack_bottom = 0x7f13dc1d9dd8 thread_stack 0x49000 mysqld(my_print_stacktrace+0x2e)[0x5569b87e4e6e] mysqld(handle_fatal_signal+0x515)[0x5569b827d885] /lib/x86_64-linux-gnu/libpthread.so.0(+0x12890)[0x7f13e2f0f890] mysqld(_ZN10Item_field10fix_fieldsEP3THDPP4Item+0x219)[0x5569b82a1089] mysqld(_ZN20Item_direct_view_ref10fix_fieldsEP3THDPP4Item+0x113)[0x5569b82a2003] mysqld(_ZN9Item_func10fix_fieldsEP3THDPP4Item+0x147)[0x5569b82da067] mysqld(_ZN9Item_cond10fix_fieldsEP3THDPP4Item+0x424)[0x5569b82b18b4] mysqld(_ZN4JOIN14optimize_innerEv+0x705)[0x5569b80f1dc5] mysqld(_ZN4JOIN8optimizeEv+0x37)[0x5569b80f3fb7] mysqld(_Z22mysql_derived_optimizeP3THDP3LEXP10TABLE_LIST+0xef)[0x5569b8067ebf] mysqld(_Z27mysql_handle_single_derivedP3LEXP10TABLE_LISTj+0xb1)[0x5569b8067771] mysqld(_ZN4JOIN14optimize_innerEv+0x63e)[0x5569b80f1cfe] mysqld(_ZN4JOIN8optimizeEv+0x37)[0x5569b80f3fb7] mysqld(_Z12mysql_selectP3THDP10TABLE_LISTjR4ListI4ItemEPS4_jP8st_orderS9_S7_S9_yP13select_resultP18st_select_lex_unitP13st_select_lex+0x856)[0x5569b80f5d86] mysqld(_Z13handle_selectP3THDP3LEXP13select_resultm+0x14d)[0x5569b80f5f8d] mysqld(_Z21mysql_execute_commandP3THD+0x7d57)[0x5569b80a5127] mysqld(_Z11mysql_parseP3THDPcjP12Parser_statebb+0x20a)[0x5569b80a56ba] mysqld(_Z16dispatch_command19enum_server_commandP3THDPcjbb+0x1c57)[0x5569b80a8037] mysqld(_Z10do_commandP3THD+0x178)[0x5569b80a8df8] mysqld(_Z24do_handle_one_connectionP7CONNECT+0x33e)[0x5569b817b1de] mysqld(handle_one_connection+0x3d)[0x5569b817b2ad] /lib/x86_64-linux-gnu/libpthread.so.0(+0x76db)[0x7f13e2f046db] /lib/x86_64-linux-gnu/libc.so.6(clone+0x3f)[0x7f13e250688f] Trying to get some variables. Some pointers may be invalid and cause the dump to abort. Query (0x7f137000f5e0): insert into `table_d` (`name`, `uuid`, `c_id`) select distinct ( case when (x2.x4 is null) then null else (substring(x2.x4, 1, 100)) end), case when (x2.x16 is not null) then x2.x17 else null end, x2.x18 from (select x19.x23 as x18, x19.x32 as x33, x19.x81 as x4, x19.x90 as x16, x19.x139 as x17, x19.x140 as x141, (case when (x216.`d_id` is null) then null else 1 end) as x217 from ( select x255.x258 as x23, x255.x264 as x32, x255.x267 as x37, x255.x293 as x81, x255.x298 as x90, x255.x323 as x139, (case when (x324.`d_id` is null) then null else 1 end) as x140 from ( select x325.`c_id` as x258, x325.`a_id` as x264, x325.`uuid` as x267, x326.`name` as x293, (case when (x327.`uuid` is null) then null else 1 end) as x298, x327.`uuid` as x323 from `table_c` x325 inner join `table_a` x326 on x325.`a_id` = x326.`a_id` left outer join `table_b` x327 on x327.`uuid` = x326.`uuid`) x255 left outer join `table_d` x324 on x324.`c_id` = x255.x258) x19 left outer join `table_d` x216 on (x19.x37 = x216.`uuid`) and false) x2 left outer join `table_d` x328 on (x2.x33 = x328.`a_id`) where (((x2.x141 is null) and (x2.x217 is null)) and (x328.`d_id` is null)) Connection ID (thread ID): 10 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,split_materialized=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. Writing a core file... Working directory at /var/lib/mysql Resource Limits: Limit Soft Limit Hard Limit Units Max cpu time unlimited unlimited seconds Max file size unlimited unlimited bytes Max data size unlimited unlimited bytes Max stack size 8388608 unlimited bytes Max core file size unlimited unlimited bytes Max resident set unlimited unlimited bytes Max processes unlimited unlimited processes Max open files 1048576 1048576 files Max locked memory 65536 65536 bytes Max address space unlimited unlimited bytes Max file locks unlimited unlimited locks Max pending signals 128407 128407 signals Max msgqueue size 819200 819200 bytes Max nice priority 0 0 Max realtime priority 0 0 Max realtime timeout unlimited unlimited us Core pattern: |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %e