- ALTER_ALGORITHM should be substituted when there is no mention of
algorithm in alter statement.
- Introduced algorithm(thd) in Alter_info. It returns the
user requested algorithm. If user doesn't specify algorithm explicitly then
it returns alter_algorithm variable.
- changed algorithm() to get_algorithm(thd) to return algorithm name for
displaying the error.
- set_requested_algorithm(algo_value) to avoid direct assignment on
requested_algorithm variable.
- Avoid direct access of requested_algorithm to encapsulate
requested_algorithm variable
Remove the separate test innodb.alter_instant, because
it can be easily mistaken for innodb.instant_alter, which
in turn is covering various instant ALTER TABLE operations.
The table option page_compression_level is something that only
affects future writes, not actually the data format. Therefore,
we can allow instant changes of this option.
Similarly, the table option page_compressed can be set on a
previously uncompressed table without rebuilding the table,
because an uncompressed page would be considered valid when
reading a page_compressed table.
Removing the page_compressed option will continue to require
the table to be rebuilt.
ha_innobase_inplace_ctx::page_compression_level: The requested
page_compression_level at the start of ALTER TABLE, or 0 if
page_compressed=OFF.
alter_options_need_rebuild(): Renamed from
create_option_need_rebuild(). Allow page_compression_level and
page_compressed to be changed as above, without rebuilding the table.
ha_innobase::check_if_supported_inplace_alter(): Allow ALGORITHM=INSTANT
for ALTER_OPTIONS if the table is not to be rebuilt. If rebuild is
needed, set ha_alter_info->unsupported_reason.
innobase_page_compression_try(): Update SYS_TABLES.TYPE according
to the table flags, for an instant change of page_compression_level
or page_compressed.
commit_cache_norebuild(): Adjust dict_table_t::flags, fil_space_t::flags
and (if needed) FSP_SPACE_FLAGS if page_compression_level was specified.
Introduced new alter algorithm type called NOCOPY & INSTANT for
inplace alter operation.
NOCOPY - Algorithm refuses any alter operation that would
rebuild the clustered index. It is a subset of INPLACE algorithm.
INSTANT - Algorithm allow any alter operation that would
modify only meta data. It is a subset of NOCOPY algorithm.
Introduce new variable called alter_algorithm. The values are
DEFAULT(0), COPY(1), INPLACE(2), NOCOPY(3), INSTANT(4)
Message to deprecate old_alter_table variable and make it alias
for alter_algorithm variable.
alter_algorithm variable for slave is always set to default.
