2020-12-07 14:16:05 0 [Note] Added new Master_info '' to hash table
2020-12-07 14:16:05 0 [Note] mysqld: ready for connections.
Version: '10.3.27-MariaDB-1:10.3.27+maria~focal'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  mariadb.org binary distribution
2020-12-07 14:16:05 0 [Note] InnoDB: Buffer pool(s) load completed at 201207 14:16:05
201207 14:17:10 [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: 10.3.27-MariaDB-1:10.3.27+maria~focal
key_buffer_size=134217728
read_buffer_size=2097152
max_used_connections=21
max_threads=102
thread_count=65
It is possible that mysqld could use up to 
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 760035 K  bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x7f74e0000c48
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 = 0x7f75ac1bedd8 thread_stack 0x49000
mysqld(my_print_stacktrace+0x32)[0x55e18844a552]
mysqld(handle_fatal_signal+0x55d)[0x55e187f25a6d]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x153c0)[0x7f75bfafe3c0]
/usr/lib/mysql/plugin/ha_spider.so(_Z34spider_rm_sys_tmp_table_for_resultP3THDP5TABLEP15TMP_TABLE_PARAM+0x3c)[0x7f75b940de6c]
/usr/lib/mysql/plugin/ha_spider.so(_Z21spider_db_free_resultP9ha_spiderb+0x15a)[0x7f75b941b87a]
/usr/lib/mysql/plugin/ha_spider.so(_ZN9ha_spider5resetEv+0x172)[0x7f75b94791f2]
mysqld(+0xcc66ae)[0x55e1884116ae]
mysqld(_Z18close_thread_tableP3THDPP5TABLE+0xc9)[0x55e187ccc7c9]
mysqld(_Z19close_thread_tablesP3THD+0x18b)[0x55e187ccc9fb]
mysqld(_Z21mysql_execute_commandP3THD+0xc7e)[0x55e187d2bffe]
mysqld(_Z11mysql_parseP3THDPcjP12Parser_statebb+0x1f3)[0x55e187d33fa3]
mysqld(_Z16dispatch_command19enum_server_commandP3THDPcjbb+0x104d)[0x55e187d3636d]
mysqld(_Z10do_commandP3THD+0x12d)[0x55e187d3830d]
mysqld(_Z24do_handle_one_connectionP7CONNECT+0x246)[0x55e187e1f186]
mysqld(handle_one_connection+0x3f)[0x55e187e1f35f]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x9609)[0x7f75bfaf2609]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x43)[0x7f75bf6e7293]

Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (0x7f74e0011838): select * from POLOHY where id_obj = 24667 and timeunit >= '2020-01-01 10:00' and timeunit < '2020-01-13 12:00'

Connection ID (thread ID): 870
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 https://mariadb.com/kb/en/how-to-produce-a-full-stack-trace-for-mysqld/ 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         16777216             16777216             bytes     
Max address space         unlimited            unlimited            bytes     
Max file locks            unlimited            unlimited            locks     
Max pending signals       127145               127145               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/share/apport/apport %p %s %c %d %P