MDEV-10134 Add full support for DEFAULT
- Added support for using tables with MySQL 5.7 virtual fields,
including MySQL 5.7 syntax
- Better error messages also for old cases
- CREATE ... SELECT now also updates timestamp columns
- Blob can now have default values
- Added new system variable "check_constraint_checks", to turn of
CHECK constraint checking if needed.
- Removed some engine independent tests in suite vcol to only test myisam
- Moved some tests from 'include' to 't'. Should some day be done for all tests.
- FRM version increased to 11 if one uses virtual fields or constraints
- Changed to use a bitmap to check if a field has got a value, instead of
setting HAS_EXPLICIT_VALUE bit in field flags
- Expressions can now be up to 65K in total
- Ensure we are not refering to uninitialized fields when handling virtual fields or defaults
- Changed check_vcol_func_processor() to return a bitmap of used types
- Had to change some functions that calculated cached value in fix_fields to do
this in val() or getdate() instead.
- store_now_in_TIME() now takes a THD argument
- fill_record() now updates default values
- Add a lookahead for NOT NULL, to be able to handle DEFAULT 1+1 NOT NULL
- Automatically generate a name for constraints that doesn't have a name
- Added support for ALTER TABLE DROP CONSTRAINT
- Ensure that partition functions register virtual fields used. This fixes
some bugs when using virtual fields in a partitioning function
Decimals with float, double and decimal now works the following way:
- DECIMAL_NOT_SPECIFIED is used when declaring DECIMALS without a firm number
of decimals. It's only used in asserts and my_decimal_int_part.
- FLOATING_POINT_DECIMALS (31) is used to mark that a FLOAT or DOUBLE
was defined without decimals. This is regarded as a floating point value.
- Max decimals allowed for FLOAT and DOUBLE is FLOATING_POINT_DECIMALS-1
- Clients assumes that float and double with decimals >= NOT_FIXED_DEC are
floating point values (no decimals)
- In the .frm decimals=FLOATING_POINT_DECIMALS are used to define
floating point for float and double (31, like before)
To ensure compatibility with old clients we do:
- When storing float and double, we change NOT_FIXED_DEC to
FLOATING_POINT_DECIMALS.
- When creating fields from .frm we change for float and double
FLOATING_POINT_DEC to NOT_FIXED_DEC
- When sending definition for a float/decimal field without decimals
to the client as part of a result set we convert NOT_FIXED_DEC to
FLOATING_POINT_DECIMALS.
- variance() and std() has changed to limit the decimals to
FLOATING_POINT_DECIMALS -1 to not get the double converted floating point.
(This was to preserve compatiblity)
- FLOAT and DOUBLE still have 30 as max number of decimals.
Bugs fixed:
variance() printed more decimals than we support for double values.
New behaviour:
- Strings now have 38 decimals instead of 30 when converted to decimal
- CREATE ... SELECT with a decimal with > 30 decimals will create a column
with a smaller range than before as we are trying to preserve the number of
decimals.
Other changes
- We are now using the obsolete bit FIELDFLAG_LEFT_FULLSCREEN to specify
decimals > 31
- NOT_FIXED_DEC is now declared in one place
- For clients, NOT_FIXED_DEC is always 31 (to ensure compatibility).
On the server NOT_FIXED_DEC is DECIMAL_NOT_SPECIFIED (39)
- AUTO_SEC_PART_DIGITS is taken from DECIMAL_NOT_SPECIFIED
- DOUBLE conversion functions are now using DECIMAL_NOT_SPECIFIED instead of
NOT_FIXED_DEC
mysqld maintains a list of TABLE objects for all temporary
tables created within a session in THD. Here each table is
represented by a TABLE object.
A query referencing a particular temporary table for more
than once, however, failed with ER_CANT_REOPEN_TABLE error
because a TABLE_SHARE was allocate together with the TABLE,
so temporary tables always had only one TABLE per TABLE_SHARE.
This patch lift this restriction by separating TABLE and
TABLE_SHARE objects and storing TABLE_SHAREs for temporary
tables in a list in THD, and TABLEs in a list within their
respective TABLE_SHAREs.
- unused TABLE_SHARE::deleting and TABLE_LIST::deleting flags were removed
- kill_delayed_threads_for_table() and intern_close_table() are now private
methods of table cache
- removed free_share flag of closefrm(): it was never used for temporary
tables and was rarely useful for regular tables
- To ensure that mallocs are marked for the correct THD, even if it's
allocated in another thread, I added the thread_id to the THD constructor
- Added st_my_thread_var to thr_lock_info_init() to avoid a call to my_thread_var
- Moved things from THD::THD() to THD::init()
- Moved some things to THD::cleanup()
- Added THD::free_connection() and THD::reset_for_reuse()
- Added THD to CONNECT::create_thd()
- Added THD::thread_dbug_id and st_my_thread_var->dbug_id. These are needed
to ensure that we have a constant thread_id used for debugging with a THD,
even if it changes thread_id (=connection_id)
- Set variables.pseudo_thread_id in constructor. Removed not needed sets.
Variant #4 of the fix.
Make ORDER BY optimization functions take into account multiple
equalities. This is done in several places:
- remove_const() checks whether we can sort the first table in the
join, or we need to put rows into temp.table and then sort.
- test_if_order_by_key() checks whether there are indexes that
can be used to produce the required ordering
- make_unireg_sortorder() constructs sort criteria for filesort.
* simplify the code at default: label
* bugfix: flush the checksum for NULL fields
(perfschema.checksum was failing)
* cleanup: put repeated code into a function
Checksum implementations contain optimizations for calculating
checksums of larger blocks of memory.
This optimization calls my_checksum on a larger block of memory
rather than calling on multiple adjacent memory as its going though
the table columns for each table row.
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.
The main.merge test case was failing when tested using row based
binlog format.
While analyzing the issue it was found the following issues:
a) The server is calling binlog related code even when a statement will
not be binlogged;
b) The child table list was not present into table structure by the time
to generate the create table statement;
c) The tables in the child table list will not be opened yet when
generating table create info using row based replication;
d) CREATE TABLE LIKE TEMP_TABLE does not preserve original table storage
engine when using row based replication;
This patch addressed all above issues.
@ sql/sql_class.h
Added a function to determine if the binary log is disabled to
the current session. This is related with issue (a) above.
@ sql/sql_table.cc
Added code to skip binary logging related code if the statement
will not be binlogged. This is related with issue (a) above.
Added code to add the children to the query list of the table that
will have its CREATE TABLE generated. This is related with issue (b)
above.
Added code to force the storage engine to be generated into the
CREATE TABLE. This is related with issue (d) above.
@ storage/myisammrg/ha_myisammrg.cc
Added a test to skip a table getting info about a child table if the
child table is not opened. This is related to issue (c) above.
fix a few cases where a successful ALTER was not binlogged:
* on errors after the completed ALTER, binlog it, then return an error
* don't let thd->killed abort open_table() after completed
online ALTER.
"Re-factor the code for post-join operations".
The patch mainly contains the code ported from mysql-5.6 and
created for two essential architectural changes:
1. WL#5558: Resolve ORDER BY execution method at the optimization stage
2. WL#6071: Inline tmp tables into the nested loops algorithm
The first task was implemented for mysql-5.6 by Ole John Aske.
It allows to make all decisions on ORDER BY operation at the optimization
stage.
The second task implemented for mysql-5.6 by Evgeny Potemkin adds JOIN_TAB
nodes for post-join operations that require temporary tables. It allows
to execute these operations within the nested loops algorithm that used to
be used before this task only for join queries. Besides these task moves
all planning on the execution of these operations from the execution phase
to the optimization phase.
Some other re-factoring changes of mysql-5.6 were pulled in, mainly because
it was easier to pull them in than roll them back. In particular all
changes concerning Ref_ptr_array were incorporated.
The port required some changes in the MariaDB code that concerned the
functionality of EXPLAIN and ANALYZE. This was done mainly by Sergey
Petrunia.
COLUMNS
ANALYSIS:
=========
A valgrind error is reported when CREATE TABLE .. SELECT
involving BIT columns triggers a column type redefinition.
In general the pack_flag is set for BIT columns in
'mysql_prepare_create_table()'. However, during the above
operation, redefined column types was handled after the
special handling for BIT columns and thus pack_flag ended
up not being set correctly triggering the valgrind error.
FIX:
====
The patch fixes this problem by setting pack_flag correctly
for BIT columns in the case of column type redefinition.
On shutdown feedback was sending a short report without creating
a THD. At that point current_thd was pointing to the already
destroyed THD from the previous full report.
backport from 10.1:
commit bfe703a
Author: Sergei Golubchik <serg@mariadb.org>
Date: Tue Feb 3 18:19:56 2015 +0100
don't let current_thd to point to a destroyed THD
Problem:
========
1) Drop table queries are re-generated by server
before writing the events(queries) into binlog
for various reasons. If table name/db name contains
a non regular characters (like latin characters),
the generated query is wrong. Hence it breaks the
replication.
2) In the edge case, when table name/db name contains
64 characters, server is throwing an assert
assert(M_TBLLEN < 128)
3) In the edge case, when db name contains 64 latin
characters, binlog content is interpreted badly
which is leading replication failure.
Analysis & Fix :
================
1) Parser reads the table name from the query and converts
it to standard charset(utf8) and stores it in table_name variable.
When drop table query is regenerated with the same table_name
variable, it should be converted back to the original charset
from standard charset(utf8).
2) Latin character takes two bytes for each character. Limit
of the identifier is 64. SYSTEM_CHARSET_MBMAXLEN is set to '3'.
So there is a possiblity that tablename/dbname contains 3 * 64.
Hence assert is changed to
(M_TBLLEN <= NAME_CHAR_LEN*SYSTEM_CHARSET_MBMAXLEN)
3) db_len in the binlog event header is taking 1 byte.
db_len is ranged from 0 to 192 bytes (3 * 64).
While reading the db_len from the event, server
is casting to uint instead of uchar which is leading
to bad db_len. This problem is fixed by changing the
cast type to uchar.
This includes fixing all utilities to not have any memory leaks,
as safemalloc warnings stopped tests from passing on MacOSX.
- Ensure that all clients takes character-set-dir, as the
libmysqlclient library will use it.
- mysql-test-run now passes character-set-dir to all external clients.
- Changed dynstr_free() so that it can be called twice (made freeing code easier)
- Changed rpl_global_gtid_slave_state to be allocated dynamicly as it
includes a mutex that needs to be initizlied/destroyed before my_end() is called.
- Removed rpl_slave_state::init() and rpl_slave_stage::deinit() as
their job are better handling by constructor and delete.
- Print alias instead of table_name in check_duplicate_key as
table_name may have been converted to lower case.
Other things:
- Fixed a case in time_to_datetime_with_warn() where we where
using && instead of & in tests
The following left in semi-improved state to keep patch size reasonable:
- Field operator new: left thd_alloc(current_thd)
- Sql_alloc operator new: left thd_alloc(thd_get_current_thd())
- Item_args constructors: left thd_alloc(thd)
- Item_func_interval::fix_length_and_dec(): no THD arg, have to call current_thd
- Item_func_dyncol_exists::val_int(): same
- Item_dyncol_get::val_str(): same
- Item_dyncol_get::val_int(): same
- Item_dyncol_get::val_real(): same
- Item_dyncol_get::val_decimal(): same
- Item_singlerow_subselect::fix_length_and_dec(): same