Hi, Rucha! On Oct 17, Rucha Deodhar wrote:

revision-id: a895fce3277 (mariadb-10.6.1-138-ga895fce3277) parent(s): c27f04ede5a author: Rucha Deodhar committer: Rucha Deodhar timestamp: 2021-10-17 17:59:11 +0530 message:

MDEV-26842: MDEV-26842: ROW_NUMBER is not set and differs from the message upon WARN_DATA_TRUNCATED produced by inplace ALTER

Analysis: When row number is passed as parameter to set_warning() it is only used for error/warning text but m_current_row_for_warning is not updated. Hence default value of m_current_row_for_warning is assumed. Fix: update m_current_row_for_warning when error/warning occurs.

diff --git a/sql/field.cc b/sql/field.cc index a5cd595f05b..048798ea509 100644 --- a/sql/field.cc +++ b/sql/field.cc @@ -11086,6 +11086,10 @@ Field::set_warning(Sql_condition::enum_warning_level level, uint code, will have table == NULL. */ THD *thd= get_thd(); + ulong row_count= current_row ? current_row + : thd->get_stmt_da()->current_row_for_warning(); + + thd->get_stmt_da()->reset_current_row_for_warning(row_count);

Isn't it a bit confusing, why do you set current_row_for_warning to its own actual value? May be it'd be clearer to if (current_row) thd->get_stmt_da()->reset_current_row_for_warning(current_row); And also, please, mention either here or in the commit comment that it's for INPLACE alter, where the server cannot know what row has generated the warning, so the value of current_row is supplied by the engine.

if (thd->count_cuted_fields > CHECK_FIELD_EXPRESSION) { thd->cuted_fields+= cut_increment;

Regards, Sergei VP of MariaDB Server Engineering and security@mariadb.org