mark big_tables deprecated, the server can put temp tables on disk
as needed avoiding "table full" errors.
in case someone would really need to force a tmp table to be created
on disk from the start and for testing allow tmp_memory_table_size
to be set to 0.
fix tests to use that instead (and add a test that it actually
works).
make sure in-memory TREE size limit is never 0 (it's [ab]using
tmp_memory_table_size at the moment)
remove few sys_vars.*_basic tests
Step 1: Removal of ORDER BY [LIMIT] from the subquery should be done
earlier and for broader class of subqueries.
The rewrite was done in Item_in_subselect::select_in_like_transformer(),
but this had problems:
- It didn't cover EXISTS subqueries
- It covered IN-subqueries, but was done after the semi-join transformation
was considered inapplicable, because ORDER BY was present.
Remaining issue:
- EXISTS->IN transformation happens before
check_and_do_in_subquery_rewrites() is called, so it is still prevented
by the present ORDER BY.
Parenthesis around table names and derived tables should be allowed
in FROM clauses and some other context as it was in earlier versions.
Returned test queries that used such parenthesis in 10.3 to their
original form. Adjusted test results accordingly.
The MDEV-17262 commit 26432e49d3
was skipped. In Galera 4, the implementation would seem to require
changes to the streaming replication.
In the tests archive.rnd_pos main.profiling, disable_ps_protocol
for SHOW STATUS and SHOW PROFILE commands until MDEV-18974
has been fixed.
This patch contains a full implementation of the optimization
that allows to use in-memory rowid / primary filters built for range
conditions over indexes. In many cases usage of such filters reduce
the number of disk seeks spent for fetching table rows.
In this implementation the choice of what possible filter to be applied
(if any) is made purely on cost-based considerations.
This implementation re-achitectured the partial implementation of
the feature pushed by Galina Shalygina in the commit
8d5a11122c.
Besides this patch contains a better implementation of the generic
handler function handler::multi_range_read_info_const() that
takes into account gaps between ranges when calculating the cost of
range index scans. It also contains some corrections of the
implementation of the handler function records_in_range() for MyISAM.
This patch supports the feature for InnoDB and MyISAM.
