Before MDEV-12113 (MariaDB Server 10.1.25), on shutdown InnoDB would write
the current LSN to the first page of each file of the system tablespace.
This is incompatible with MariaDB's InnoDB table encryption, because
encryption repurposed the field for an encryption key ID and checksum.
buf_page_is_corrupted(): For the InnoDB system tablespace, skip
FIL_PAGE_FILE_FLUSH_LSN when checking if a page is all zero,
because the first page of each file in the system tablespace can
contain nonzero bytes in the field.
The test case for reproducing MDEV-14126 demonstrates that InnoDB can
end up with an index tree where a non-leaf page has only one child page.
The test case innodb.innodb_bug14676111 demonstrates that such pages
are sometimes unavoidable, because InnoDB does not implement any sort
of B-tree rotation.
But, there is no reason to allow a root page with only one child page.
btr_cur_node_ptr_delete(): Replaces btr_node_ptr_delete().
btr_page_get_father(): Declare globally.
btr_discard_only_page_on_level(): Declare with ATTRIBUTE_COLD.
It turns out that this function is not covered by the
innodb.innodb_bug14676111 test case after all.
btr_discard_page(): If the root page ends up having only one child
page, shrink the tree by invoking btr_lift_page_up().
The predicate page_is_root(), which was added in MariaDB Server 10.2.2,
is based on a wrong assumption.
Under some circumstances, InnoDB can transform B-trees into a degenerate
state where a non-leaf page has no sibling pages. Because of this,
we cannot assume that a page that has no siblings is the root page.
This bug will be tracked as MDEV-19022.
Because of the bug that may affect many InnoDB data files, we must remove
and replace the wrong predicate. Using the wrong predicate can cause
corruption. A leaf page is not allowed to be empty except if it is the
root page, and the entire table is empty.
MariaDB before MDEV-5800 in version 10.2.2 did not support
indexed virtual columns. Non-persistent virtual columns were
hidden from storage engines. Only starting with MDEV-5800, InnoDB
would create internal metadata on virtual columns.
Similar to what was done in MDEV-18084 and MDEV-18960, we adjust two more
code paths for the old tables.
ha_innobase::build_template(): Do not invoke
dict_index_contains_col_or_prefix() for virtual columns if InnoDB
does not store the metadata.
innobase_build_col_map(): Relax an assertion about the number of columns.
ha_innobase::omits_virtual_cols(): Renamed from omits_virtual_cols().
Simulate slow statements only for COM_QUERY and COM_STMT_EXECUTE commands,
to exclude mysqld_stmt_prepare() and mysqld_stmt_close() entries from the log,
as they are not relevant for log_slow_debug.test. This simplifies the test.
The test innodb.recovery_shutdown would occasionally fail,
because recovered incomplete transactions would be conflicting
with DROP TABLE, causing the background drop table queue to be invoked.
Add a slow shutdown before dropping the tables, so that the
recovered transactions will be rolled back. Starting with MDEV-14705,
normal shutdown would abort the rollback of recovered transactions.
