Hi, Aleksey, On Jun 27, Aleksey Midenkov wrote:

revision-id: 59aafa4ee46 (mariadb-10.6.22-50-g59aafa4ee46) parent(s): 1221f49f312 author: Aleksey Midenkov committer: Aleksey Midenkov timestamp: 2025-06-04 23:42:36 +0300 message:

MDEV-33633 Trigger tries to access already dropped view

diff --git a/mysql-test/main/ps_ddl.result b/mysql-test/main/ps_ddl.result index 35998c05dc9..ceb85835623 100644 --- a/mysql-test/main/ps_ddl.result +++ b/mysql-test/main/ps_ddl.result @@ -333,7 +333,7 @@ a drop view v1; create view v1 as select a from t3; insert into t1 (a) values (6); -ERROR 42S02: Table 'test.t2' doesn't exist +ERROR HY000: Table definition has changed, please retry transaction

Is it possible to the fallback and reopen here? This is a rather unexpected error, particularly when no transactions are involved.

diff --git a/sql/sql_base.cc b/sql/sql_base.cc index 1a4fa315c3c..c89e88d0f03 100644 --- a/sql/sql_base.cc +++ b/sql/sql_base.cc @@ -1737,6 +1737,18 @@ bool is_locked_view(THD *thd, TABLE_LIST *t) DBUG_RETURN(FALSE); }

+ Reprepare_observer reprepare_observer; + auto scope_exit= make_scope_exit( + [thd]() mutable { thd->m_reprepare_observer= NULL; }, + false); + if (!thd->m_reprepare_observer) + { + reprepare_observer.reset_reprepare_observer(); + reprepare_observer.error_code= ER_TABLE_DEF_CHANGED; + thd->m_reprepare_observer= &reprepare_observer; + scope_exit.engage(); + }

And you didn't use SCOPE_EXIT to use a manual engage? Would be clearer, I'd say, to use SCOPE_EXIT and have an if() inside, like if (m_reprepare_observer == &reprepare_observer). But ok, as you like.

if (!tdc_open_view(thd, t, CHECK_METADATA_VERSION)) { DBUG_ASSERT(t->view != 0); @@ -3059,9 +3071,7 @@ bool tdc_open_view(THD *thd, TABLE_LIST *table_list, uint flags)

DBUG_ASSERT(share->is_view);

- err= mysql_make_view(thd, share, table_list, (flags & OPEN_VIEW_NO_PARSE)); - - if (!err && (flags & CHECK_METADATA_VERSION)) + if (flags & CHECK_METADATA_VERSION) { /* Check TABLE_SHARE-version of view only if we have been instructed to do @@ -3076,6 +3086,8 @@ bool tdc_open_view(THD *thd, TABLE_LIST *table_list, uint flags) goto ret; }

+ err= mysql_make_view(thd, share, table_list, (flags & OPEN_VIEW_NO_PARSE));

But this one - I don't understand how it works. mysql_make_view() reads the view frm which contains versions that are checked by check_and_update_table_version(). How can check_and_update_table_version() work before mysql_make_view()?

ret: tdc_release_share(share);

diff --git a/sql/table.cc b/sql/table.cc index 9bbc29d4ecf..6d2a80aeace 100644 --- a/sql/table.cc +++ b/sql/table.cc @@ -5799,6 +5799,12 @@ void TABLE::init(THD *thd, TABLE_LIST *tl) DBUG_ASSERT(!auto_increment_field_not_null); auto_increment_field_not_null= FALSE;

+ tl->view= NULL; + tl->derived= NULL; + tl->derived_type= VIEW_ALGORITHM_UNDEFINED; + tl->updatable= true; + tl->effective_with_check= VIEW_CHECK_NONE; +

I agree it's conceptually correct and for the new table these fields should be reset. But it's rather unexpected that TABLE::init() modifies its arguments. Could this reinitialization be done somewhere else? Regards, Sergei Chief Architect, MariaDB Server and security@mariadb.org