This replxx object is pretty heavy and in debug build may slow down [1]
(although I cannot confirm 0.5s delay for each query in debug build) the
client and besides it is not required since ClickHouse-Extras/replxx#10,
which changes the behaviour of history_save(), and now it will not
update current session anymore, only save the history to the disk.
[1]: https://github.com/ClickHouse/ClickHouse/pull/13086#issuecomment-667719026
This will fix style check error:
/place/sandbox-data/tasks/4/8/795063184/ClickHouse/tests/queries/0_stateless/01521_connections_with_failover_max_tries_0.reference
/place/sandbox-data/tasks/4/8/795063184/ClickHouse/tests/queries/0_stateless/01521_connections_with_failover_max_tries_0.sql
Tests should not be named with "fail" in their names. It makes looking at the results less convenient when you search for "fail" substring in browser.
Materialized view drop the inner table (if any) drop the drop() method,
and this will lead to essure recursive drop() from the drop worker
thread, which will hang:
3 std::__1::condition_variable::wait<> ()
4 DB::DatabaseCatalog::waitTableFinallyDropped (this=0x7ffff7831500, uuid=...) at ../src/Interpreters/DatabaseCatalog.cpp:828
5 DB::InterpreterDropQuery::executeToTable (this=this@entry=0x7fff16ff88a0, table_id_=..., query=...) at ../src/Interpreters/InterpreterDropQuery.cpp:135
6 DB::InterpreterDropQuery::execute (this=this@entry=0x7fff16ff88a0) at ../contrib/libcxx/include/string:1474
7 DB::executeDropQuery (kind=kind@entry=DB::ASTDropQuery::Drop, global_context=..., target_table_id=...) at ../src/Storages/StorageMaterializedView.cpp:156
8 DB::StorageMaterializedView::drop (this=0x7ffefc348f40) at ../src/Storages/StorageMaterializedView.cpp:169
9 DB::DatabaseCatalog::dropTableFinally (this=this@entry=0x7ffff7831500, table=...) at ../src/Interpreters/DatabaseCatalog.cpp:775
10 DB::DatabaseCatalog::dropTableDataTask (this=0x7ffff7831500) at ../src/Interpreters/DatabaseCatalog.cpp:745
Fix this by dropping the inner table just before scheduling job the the
drop worker thread.
