With innodb_default_row_format=redundant, InnoDB would crash when
using table options that are incompatible with ROW_FORMAT=REDUNDANT.
create_table_info_t::m_default_row_format: Cache the value of
innodb_default_row_format.
create_table_info_t::check_table_options(): Validate ROW_TYPE_DEFAULT
with m_default_row_format.
create_table_info_t::innobase_table_flags(): Use the
cached m_default_row_format.
create_table_info_t: Never read m_form->s->row_type.
Use m_create_info->row_type instead.
dict_tf_set(): Never set invalid flags for ROW_FORMAT=REDUNDANT.
ha_innobase::truncate(): Set info.row_type based on the ROW_FORMAT
of the current table.
InnoDB in Debian uses utf8mb4 as default character set since
version 10.0.20-2. This leads to major pain due to keys longer
than 767 bytes.
MariaDB 10.2 (and MySQL 5.7) introduced the setting
innodb_default_row_format that is DYNAMIC by default. These
versions also changed the default values of the parameters
innodb_large_prefix=ON and innodb_file_format=Barracuda.
This would allow longer column index prefixes to be created.
The original purpose of these parameters was to allow InnoDB
to be downgraded to MySQL 5.1, which is long out of support.
Every InnoDB version since MySQL 5.5 does support operation
with the relaxed limits.
We backport the parameter innodb_default_row_format to
MariaDB 10.1, but we will keep its default value at COMPACT.
This allows MariaDB 10.1 to be configured so that CREATE TABLE
is less likely to encounter a problem with the limitation:
loose_innodb_large_prefix=ON
loose_innodb_default_row_format=DYNAMIC
(Note that the setting innodb_large_prefix was deprecated in
MariaDB 10.2 and removed in MariaDB 10.3.)
The only observable difference in the behaviour with the default
settings should be that ROW_FORMAT=DYNAMIC tables can be created
both in the system tablespace and in .ibd files, no matter what
innodb_file_format has been assigned to. Unlike MariaDB 10.2,
we are not changing the default value of innodb_file_format,
so ROW_FORMAT=COMPRESSED tables cannot be created without
changing the parameter.
