This task deals with packing the non-sorted fields (or addon fields).
This would lead to efficient usage of the memory allocated for the sort buffer.
The changes brought by this feature are
1) Sort buffers would have records of variable length
2) Each record in the sort buffer would be stored like
<sort_key1><sort_key2>....<addon_length><null_bytes><field1><field2>....
addon_length is the extra bytes that are required to store the variable
length of addon field across different records.
3) Changes in rr_unpack_from_buffer and rr_from_tempfile to take into account
the variable length of records.
Ported WL#1509 Pack values of non-sorted fields in the sort buffer from
MySQL by Tor Didriksen
There were two newly enabled warnings:
1. cast for a function pointers. Affected sql_analyse.h, mi_write.c
and ma_write.cc, mf_iocache-t.cc, mysqlbinlog.cc, encryption.cc, etc
2. memcpy/memset of nontrivial structures. Fixed as:
* the warning disabled for InnoDB
* TABLE, TABLE_SHARE, and TABLE_LIST got a new method reset() which
does the bzero(), which is safe for these classes, but any other
bzero() will still cause a warning
* Table_scope_and_contents_source_st uses `TABLE_LIST *` (trivial)
instead of `SQL_I_List<TABLE_LIST>` (not trivial) so it's safe to
bzero now.
* added casts in debug_sync.cc and sql_select.cc (for JOIN)
* move assignment method for MDL_request instead of memcpy()
* PARTIAL_INDEX_INTERSECT_INFO::init() instead of bzero()
* remove constructor from READ_RECORD() to make it trivial
* replace some memcpy() with c++ copy assignments
filesort and init_read_record() for the same table.
This will simplify code for WINDOW FUNCTIONS (MDEV-6115)
- Filesort_info renamed to SORT_INFO and moved to filesort.h
- filesort now returns SORT_INFO
- init_read_record() now takes a SORT_INFO parameter.
- unique declaration is moved to uniques.h
- subselect caching of buffers is now more explicit than before
- filesort_buffer is now reusable even if rec_length has changed.
- filsort_free_buffers() and free_io_cache() calls are removed
- Remove one malloc() when using get_addon_fields()
Other things:
- Added --debug-assert-on-not-freed-memory option to make it easier to
debug some not-freed-memory issues.
Assertion `inited==INDEX' failed in int handler::ha_index_first(uchar*)
The crash was because errors from init_read_record_idx() was not taken care of.
The reason for the failure was a bug in an include file on debian that causes 'struct stat'
to have different sized depending on the environment.
This patch fixes so that we always include my_global.h or my_config.h before we include any other files.
Other things:
- Removed #include <my_global.h> in some include files; Better to always do this at the top level to have as few
"always-include-this-file-first' files as possible.
- Removed usage of some include files that where already included by my_global.h or by other files.
client/mysql_plugin.c:
Use my_global.h first
client/mysqlslap.c:
Remove duplicated include files
extra/comp_err.c:
Remove duplicated include files
include/m_string.h:
Remove duplicated include files
include/maria.h:
Remove duplicated include files
libmysqld/emb_qcache.cc:
Use my_global.h first
plugin/semisync/semisync.h:
Use my_pthread.h first
sql/datadict.cc:
Use my_global.h first
sql/debug_sync.cc:
Use my_global.h first
sql/derror.cc:
Use my_global.h first
sql/des_key_file.cc:
Use my_global.h first
sql/discover.cc:
Use my_global.h first
sql/event_data_objects.cc:
Use my_global.h first
sql/event_db_repository.cc:
Use my_global.h first
sql/event_parse_data.cc:
Use my_global.h first
sql/event_queue.cc:
Use my_global.h first
sql/event_scheduler.cc:
Use my_global.h first
sql/events.cc:
Use my_global.h first
sql/field.cc:
Use my_global.h first
Remove duplicated include files
sql/field_conv.cc:
Use my_global.h first
sql/filesort.cc:
Use my_global.h first
Remove duplicated include files
sql/gstream.cc:
Use my_global.h first
sql/ha_ndbcluster.cc:
Use my_global.h first
sql/ha_ndbcluster_binlog.cc:
Use my_global.h first
sql/ha_ndbcluster_cond.cc:
Use my_global.h first
sql/ha_partition.cc:
Use my_global.h first
sql/handler.cc:
Use my_global.h first
sql/hash_filo.cc:
Use my_global.h first
sql/hostname.cc:
Use my_global.h first
sql/init.cc:
Use my_global.h first
sql/item.cc:
Use my_global.h first
sql/item_buff.cc:
Use my_global.h first
sql/item_cmpfunc.cc:
Use my_global.h first
sql/item_create.cc:
Use my_global.h first
sql/item_geofunc.cc:
Use my_global.h first
sql/item_inetfunc.cc:
Use my_global.h first
sql/item_row.cc:
Use my_global.h first
sql/item_strfunc.cc:
Use my_global.h first
sql/item_subselect.cc:
Use my_global.h first
sql/item_sum.cc:
Use my_global.h first
sql/item_timefunc.cc:
Use my_global.h first
sql/item_xmlfunc.cc:
Use my_global.h first
sql/key.cc:
Use my_global.h first
sql/lock.cc:
Use my_global.h first
sql/log.cc:
Use my_global.h first
sql/log_event.cc:
Use my_global.h first
sql/log_event_old.cc:
Use my_global.h first
sql/mf_iocache.cc:
Use my_global.h first
sql/mysql_install_db.cc:
Remove duplicated include files
sql/mysqld.cc:
Remove duplicated include files
sql/net_serv.cc:
Remove duplicated include files
sql/opt_range.cc:
Use my_global.h first
sql/opt_subselect.cc:
Use my_global.h first
sql/opt_sum.cc:
Use my_global.h first
sql/parse_file.cc:
Use my_global.h first
sql/partition_info.cc:
Use my_global.h first
sql/procedure.cc:
Use my_global.h first
sql/protocol.cc:
Use my_global.h first
sql/records.cc:
Use my_global.h first
sql/records.h:
Don't include my_global.h
Better to do this at the upper level
sql/repl_failsafe.cc:
Use my_global.h first
sql/rpl_filter.cc:
Use my_global.h first
sql/rpl_gtid.cc:
Use my_global.h first
sql/rpl_handler.cc:
Use my_global.h first
sql/rpl_injector.cc:
Use my_global.h first
sql/rpl_record.cc:
Use my_global.h first
sql/rpl_record_old.cc:
Use my_global.h first
sql/rpl_reporting.cc:
Use my_global.h first
sql/rpl_rli.cc:
Use my_global.h first
sql/rpl_tblmap.cc:
Use my_global.h first
sql/rpl_utility.cc:
Use my_global.h first
sql/set_var.cc:
Added comment
sql/slave.cc:
Use my_global.h first
sql/sp.cc:
Use my_global.h first
sql/sp_cache.cc:
Use my_global.h first
sql/sp_head.cc:
Use my_global.h first
sql/sp_pcontext.cc:
Use my_global.h first
sql/sp_rcontext.cc:
Use my_global.h first
sql/spatial.cc:
Use my_global.h first
sql/sql_acl.cc:
Use my_global.h first
sql/sql_admin.cc:
Use my_global.h first
sql/sql_analyse.cc:
Use my_global.h first
sql/sql_audit.cc:
Use my_global.h first
sql/sql_base.cc:
Use my_global.h first
sql/sql_binlog.cc:
Use my_global.h first
sql/sql_bootstrap.cc:
Use my_global.h first
Use my_global.h first
sql/sql_cache.cc:
Use my_global.h first
sql/sql_class.cc:
Use my_global.h first
sql/sql_client.cc:
Use my_global.h first
sql/sql_connect.cc:
Use my_global.h first
sql/sql_crypt.cc:
Use my_global.h first
sql/sql_cursor.cc:
Use my_global.h first
sql/sql_db.cc:
Use my_global.h first
sql/sql_delete.cc:
Use my_global.h first
sql/sql_derived.cc:
Use my_global.h first
sql/sql_do.cc:
Use my_global.h first
sql/sql_error.cc:
Use my_global.h first
sql/sql_explain.cc:
Use my_global.h first
sql/sql_expression_cache.cc:
Use my_global.h first
sql/sql_handler.cc:
Use my_global.h first
sql/sql_help.cc:
Use my_global.h first
sql/sql_insert.cc:
Use my_global.h first
sql/sql_lex.cc:
Use my_global.h first
sql/sql_load.cc:
Use my_global.h first
sql/sql_locale.cc:
Use my_global.h first
sql/sql_manager.cc:
Use my_global.h first
sql/sql_parse.cc:
Use my_global.h first
sql/sql_partition.cc:
Use my_global.h first
sql/sql_plugin.cc:
Added comment
sql/sql_prepare.cc:
Use my_global.h first
sql/sql_priv.h:
Added error if we use this before including my_global.h
This check is here becasue so many files includes sql_priv.h first.
sql/sql_profile.cc:
Use my_global.h first
sql/sql_reload.cc:
Use my_global.h first
sql/sql_rename.cc:
Use my_global.h first
sql/sql_repl.cc:
Use my_global.h first
sql/sql_select.cc:
Use my_global.h first
sql/sql_servers.cc:
Use my_global.h first
sql/sql_show.cc:
Added comment
sql/sql_signal.cc:
Use my_global.h first
sql/sql_statistics.cc:
Use my_global.h first
sql/sql_table.cc:
Use my_global.h first
sql/sql_tablespace.cc:
Use my_global.h first
sql/sql_test.cc:
Use my_global.h first
sql/sql_time.cc:
Use my_global.h first
sql/sql_trigger.cc:
Use my_global.h first
sql/sql_udf.cc:
Use my_global.h first
sql/sql_union.cc:
Use my_global.h first
sql/sql_update.cc:
Use my_global.h first
sql/sql_view.cc:
Use my_global.h first
sql/sys_vars.cc:
Added comment
sql/table.cc:
Use my_global.h first
sql/thr_malloc.cc:
Use my_global.h first
sql/transaction.cc:
Use my_global.h first
sql/uniques.cc:
Use my_global.h first
sql/unireg.cc:
Use my_global.h first
sql/unireg.h:
Removed inclusion of my_global.h
storage/archive/ha_archive.cc:
Added comment
storage/blackhole/ha_blackhole.cc:
Use my_global.h first
storage/csv/ha_tina.cc:
Use my_global.h first
storage/csv/transparent_file.cc:
Use my_global.h first
storage/federated/ha_federated.cc:
Use my_global.h first
storage/federatedx/federatedx_io.cc:
Use my_global.h first
storage/federatedx/federatedx_io_mysql.cc:
Use my_global.h first
storage/federatedx/federatedx_io_null.cc:
Use my_global.h first
storage/federatedx/federatedx_txn.cc:
Use my_global.h first
storage/heap/ha_heap.cc:
Use my_global.h first
storage/innobase/handler/handler0alter.cc:
Use my_global.h first
storage/maria/ha_maria.cc:
Use my_global.h first
storage/maria/unittest/ma_maria_log_cleanup.c:
Remove duplicated include files
storage/maria/unittest/test_file.c:
Added comment
storage/myisam/ha_myisam.cc:
Move sql_plugin.h first as this includes my_global.h
storage/myisammrg/ha_myisammrg.cc:
Use my_global.h first
storage/oqgraph/oqgraph_thunk.cc:
Use my_config.h and my_global.h first
One could not include my_global.h before oqgraph_thunk.h (don't know why)
storage/spider/ha_spider.cc:
Use my_global.h first
storage/spider/hs_client/config.cpp:
Use my_global.h first
storage/spider/hs_client/escape.cpp:
Use my_global.h first
storage/spider/hs_client/fatal.cpp:
Use my_global.h first
storage/spider/hs_client/hstcpcli.cpp:
Use my_global.h first
storage/spider/hs_client/socket.cpp:
Use my_global.h first
storage/spider/hs_client/string_util.cpp:
Use my_global.h first
storage/spider/spd_conn.cc:
Use my_global.h first
storage/spider/spd_copy_tables.cc:
Use my_global.h first
storage/spider/spd_db_conn.cc:
Use my_global.h first
storage/spider/spd_db_handlersocket.cc:
Use my_global.h first
storage/spider/spd_db_mysql.cc:
Use my_global.h first
storage/spider/spd_db_oracle.cc:
Use my_global.h first
storage/spider/spd_direct_sql.cc:
Use my_global.h first
storage/spider/spd_i_s.cc:
Use my_global.h first
storage/spider/spd_malloc.cc:
Use my_global.h first
storage/spider/spd_param.cc:
Use my_global.h first
storage/spider/spd_ping_table.cc:
Use my_global.h first
storage/spider/spd_sys_table.cc:
Use my_global.h first
storage/spider/spd_table.cc:
Use my_global.h first
storage/spider/spd_trx.cc:
Use my_global.h first
storage/xtradb/handler/handler0alter.cc:
Use my_global.h first
storage/xtradb/handler/i_s.cc:
Use my_global.h first
use limit efficiently
Bug #36569: UPDATE ... WHERE ... ORDER BY... always does a
filesort even if not required
Also two bugs reported after QA review (before the commit
of bugs above to public trees, no documentation needed):
Bug #53737: Performance regressions after applying patch
for bug 36569
Bug #53742: UPDATEs have no effect after applying patch
for bug 36569
Execution of single-table UPDATE and DELETE statements did not use the
same optimizer as was used in the compilation of SELECT statements.
Instead, it had an optimizer of its own that did not take into account
that you can omit sorting by retrieving rows using an index.
Extra optimization has been added: when applicable, single-table
UPDATE/DELETE statements use an existing index instead of filesort. A
corresponding SELECT query would do the former.
Also handling of the DESC ordering expression has been added when
reverse index scan is applicable.
From now on most single table UPDATE and DELETE statements show the
same disk access patterns as the corresponding SELECT query. We verify
this by comparing the result of SHOW STATUS LIKE 'Sort%
Currently the get_index_for_order function
a) checks quick select index (if any) for compatibility with the
ORDER expression list or
b) chooses the cheapest available compatible index, but only if
the index scan is cheaper than filesort.
Second way is implemented by the new test_if_cheaper_ordering
function (extracted part the test_if_skip_sort_order()).
mysql-test/r/log_state.result:
Updated result for optimized query, bug #36569.
mysql-test/r/single_delete_update.result:
Test case for bug #30584, bug #36569 and bug #53742.
mysql-test/r/update.result:
Updated result for optimized query, bug #30584.
Note:
"Handler_read_last 1" omitted, see bug 52312:
lost Handler_read_last status variable.
mysql-test/t/single_delete_update.test:
Test case for bug #30584, bug #36569 and bug #53742.
sql/opt_range.cc:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
* get_index_for_order() has been rewritten entirely and moved
to sql_select.cc
New QUICK_RANGE_SELECT::make_reverse method has been added.
sql/opt_range.h:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
* get_index_for_order() has been rewritten entirely and moved
to sql_select.cc
New functions:
* QUICK_SELECT_I::make_reverse()
* SQL_SELECT::set_quick()
sql/records.cc:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
* init_read_record_idx() has been modified to allow reverse index scan
New functions:
* rr_index_last()
* rr_index_desc()
sql/records.h:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
init_read_record_idx() has been modified to allow reverse index scan
sql/sql_delete.cc:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
mysql_delete: an optimization has been added to skip
unnecessary sorting with ORDER BY clause where select
result ordering is acceptable.
sql/sql_select.cc:
Bug #30584, bug #36569, bug #53737, bug #53742:
UPDATE/DELETE ... WHERE ... ORDER BY... always does a filesort
even if not required
The const_expression_in_where function has been modified
to accept both Item and Field pointers.
New functions:
* get_index_for_order()
* test_if_cheaper_ordering() has been extracted from
test_if_skip_sort_order() to share with get_index_for_order()
* simple_remove_const()
sql/sql_select.h:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
New functions:
* test_if_cheaper_ordering()
* simple_remove_const()
* get_index_for_order()
sql/sql_update.cc:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
mysql_update: an optimization has been added to skip
unnecessary sorting with ORDER BY clause where a select
result ordering is acceptable.
sql/table.cc:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
New functions:
* TABLE::update_const_key_parts()
* is_simple_order()
sql/table.h:
Bug #30584, bug #36569: UPDATE/DELETE ... WHERE ... ORDER BY...
always does a filesort even if not required
New functions:
* TABLE::update_const_key_parts()
* is_simple_order()
----------------------------------------------------------
revno: 2630.22.11
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-records
timestamp: Mon 2008-08-11 16:40:09 +0400
message:
Move read_record related functions to a new header - records.h
sql/Makefile.am:
Introduce records.h
sql/handler.h:
Forward-declare class handler (an unnecessary forward declaration
was removed from mysql_priv.h).
sql/item_subselect.cc:
Make read_record function naming more consistent.
Assign read_record function at once, no need to defer till
read_first_record invocation.
sql/mysql_priv.h:
Include records.h, previously part of structs.h
sql/records.cc:
Use records.h
sql/sql_select.h:
Update to use new declarations.
sql/structs.h:
Move declarations of READ_RECORD and related functions to records.h
