This patch is the result of running
run-clang-tidy -fix -header-filter=.* -checks='-*,modernize-use-equals-default' .
Code style changes have been done on top. The result of this change
leads to the following improvements:
1. Binary size reduction.
* For a -DBUILD_CONFIG=mysql_release build, the binary size is reduced by
~400kb.
* A raw -DCMAKE_BUILD_TYPE=Release reduces the binary size by ~1.4kb.
2. Compiler can better understand the intent of the code, thus it leads
to more optimization possibilities. Additionally it enabled detecting
unused variables that had an empty default constructor but not marked
so explicitly.
Particular change required following this patch in sql/opt_range.cc
result_keys, an unused template class Bitmap now correctly issues
unused variable warnings.
Setting Bitmap template class constructor to default allows the compiler
to identify that there are no side-effects when instantiating the class.
Previously the compiler could not issue the warning as it assumed Bitmap
class (being a template) would not be performing a NO-OP for its default
constructor. This prevented the "unused variable warning".
mysql_prepare_create_table() does my_qsort(sort_keys) on key
info. This sorting is indeterministic: a table is created with one
order and inplace alter may overwrite frm with another order. Since
inplace alter does nothing about key info for MyISAM/Aria storage
engines this results in discrepancy between frm and storage engine key
definitions.
The fix avoids the sorting of keys when no new keys added by ALTER
(and this is ok for MyISAM/Aria since it cannot add new keys inplace).
There is a case when implicit primary key may be changed when removing
NOT NULL from the part of unique key. In that case we update
modified_primary_key which is then used to not skip key sorting.
According to is_candidate_key() there is no other cases when primary
key may be changed implicitly.
Notes:
mi_keydef_write()/mi_keyseg_write() are used only in mi_create(). They
should be used in ha_inplace_alter_table() as well.
Aria corruption detection is unimplemented: maria_check_definition()
is never used!
MySQL 8.0 has this bug as well as of 8.0.26.
There is a case when implicit primary key may be changed when removing
NOT NULL from the part of unique key. In that case we update
modified_primary_key which is then used to not skip key sorting.
According to is_candidate_key() there is no other cases when primary
kay may be changed implicitly.
This is a backport of
commit fd9ca2a742 (MDEV-23295) and
commit 9a156e1a23 (MDEV-23345) to 10.3.
An instant ADD/DROP/reorder column could create a dummy table
object with the wrong ROW_FORMAT when innodb_default_row_format
was changed between CREATE TABLE and ALTER TABLE.
prepare_inplace_alter_table_dict(): If we had promised that
ALGORITHM=INPLACE is supported, we must preserve the ROW_FORMAT.
The rest of the changes are related to adding
Alter_inplace_info::inplace_supported to cache the return value of
handler::check_if_supported_inplace_alter().
An instant ADD/DROP/reorder column could create a dummy table
object with the wrong ROW_FORMAT when innodb_default_row_format
was changed between CREATE TABLE and ALTER TABLE.
prepare_inplace_alter_table_dict(): If we had promised that
ALGORITHM=INPLACE is supported, we must preserve the ROW_FORMAT.
dict_table_t::prepare_instant(): Add debug assertions to catch
ROW_FORMAT mismatch.
The rest of the changes are related to adding
Alter_inplace_info::inplace_supported to cache the return value of
handler::check_if_supported_inplace_alter().
CHECK constraint is checked by check_expression() which walks its
items and gets into Item_field::check_vcol_func_processor() to check
for conformity with foreign key list.
WITHOUT OVERLAPS is checked for same conformity in
mysql_prepare_create_table().
Long uniques are already impossible with InnoDB foreign keys. See
ER_CANT_CREATE_TABLE in test case.
2 accompanying bugs fixed (test main.constraints failed):
1. check->name.str lived on SP execute mem_root while "check" obj
itself lives on SP main mem_root. On second SP execute check->name.str
had garbage data. Fixed by allocating from thd->stmt_arena->mem_root
which is SP main mem_root.
2. CHECK_CONSTRAINT_IF_NOT_EXISTS value was mixed with
VCOL_FIELD_REF. VCOL_FIELD_REF is assigned in check_expression() and
then detected as CHECK_CONSTRAINT_IF_NOT_EXISTS in
handle_if_exists_options().
Existing cases for MDEV-16932 in main.constraints cover both fixes.
- 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
This patch adds support of RENAME INDEX operation to the ALTER TABLE
statement. Code which determines if ALTER TABLE can be done in-place
for "simple" storage engines like MyISAM, Heap and etc. was updated to
handle ALTER TABLE ... RENAME INDEX as an in-place operation. Support
for in-place ALTER TABLE ... RENAME INDEX for InnoDB was covered by
MDEV-13301.
Syntax changes
==============
A new type of <alter_specification> is added:
<rename index clause> ::= RENAME ( INDEX | KEY ) <oldname> TO <newname>
Where <oldname> and <newname> are identifiers for old name and new
name of the index.
Semantic changes
================
The result of "ALTER TABLE t1 RENAME INDEX a TO b" is a table which
contents and structure are identical to the old version of 't1' with
the only exception index 'a' being called 'b'.
Neither <oldname> nor <newname> can be "primary". The index being
renamed should exist and its new name should not be occupied
by another index on the same table.
Related to: WL#6555, MDEV-13301
This solves the following issues:
* unlike lex->m_sql_cmd and lex->sql_command, thd->query_plan_flags
is not reset in Prepared_statement::execute, it survives
till the log_slow_statement(), so slow logging behaves correctly in --ps
* using thd->query_plan_flags for both slow_log_filter and
log_slow_admin_statements means the definition of "admin" statements
for the slow log is the same no matter how it is filtered out.
main.derived_cond_pushdown: Move all 10.3 tests to the end,
trim trailing white space, and add an "End of 10.3 tests" marker.
Add --sorted_result to tests where the ordering is not deterministic.
main.win_percentile: Add --sorted_result to tests where the
ordering is no longer deterministic.
* ignore CHECK constraint for historical rows;
* FOREIGN KEY test case.
TODO:
MDEV-16301 IB: use real table name for error messages on ALTER
Closes tempesta-tech/mariadb#491
Closes#748
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.
This is done to get more free flag bits for alter_info->flags
Renamed all ALTER PARTITION defines to start with ALTER_PARTITION_
Renamed ALTER_PARTITION to ALTER_PARTITION_INFO
Renamed ALTER_TABLE_REORG to ALTER_PARTITION_TABLE_REORG
Other things:
- Shifted some ALTER_xxx defines to get empty bits at end
Main reason was to make it easier to print the above structures in
a debugger. Additional benefits is that I was able to use same
defines for both structures, which simplifes some code.
Most of the code is just removing Alter_info:: and Alter_inplace_info::
from alter table flags.
Following renames was done:
HA_ALTER_FLAGS -> alter_table_operations
CHANGE_CREATE_OPTION -> ALTER_CHANGE_CREATE_OPTION
Alter_info::ADD_INDEX -> ALTER_ADD_INDEX
DROP_INDEX -> ALTER_DROP_INDEX
ADD_UNIQUE_INDEX -> ALTER_ADD_UNIQUE_INDEX
DROP_UNIQUE_INDEx -> ALTER_DROP_UNIQUE_INDEX
ADD_PK_INDEX -> ALTER_ADD_PK_INDEX
DROP_PK_INDEX -> ALTER_DROP_PK_INDEX
Alter_info:ALTER_ADD_COLUMN -> ALTER_PARSE_ADD_COLUMN
Alter_info:ALTER_DROP_COLUMN -> ALTER_PARSE_DROP_COLUMN
Alter_inplace_info::ADD_INDEX -> ALTER_ADD_NON_UNIQUE_NON_PRIM_INDEX
Alter_inplace_info::DROP_INDEX -> ALTER_DROP_NON_UNIQUE_NON_PRIM_INDEX
Other things:
- Added typedef alter_table_operatons for alter table flags
- DROP CHECK CONSTRAINT can now be done online
- Added checks for Aria tables in alter_table_online.test
- alter_table_flags now takes an ulonglong as argument.
- Don't support online operations if checksum option is used.
- sql_lex.cc doesn't add ALTER_ADD_INDEX if index is not created
This was done in, among other things:
- thd->db and thd->db_length
- TABLE_LIST tablename, db, alias and schema_name
- Audit plugin database name
- lex->db
- All db and table names in Alter_table_ctx
- st_select_lex db
Other things:
- Changed a lot of functions to take const LEX_CSTRING* as argument
for db, table_name and alias. See init_one_table() as an example.
- Changed some function arguments from LEX_CSTRING to const LEX_CSTRING
- Changed some lists from LEX_STRING to LEX_CSTRING
- threads_mysql.result changed because process list_db wasn't always
correctly updated
- New append_identifier() function that takes LEX_CSTRING* as arguments
- Added new element tmp_buff to Alter_table_ctx to separate temp name
handling from temporary space
- Ensure we store the length after my_casedn_str() of table/db names
- Removed not used version of rename_table_in_stat_tables()
- Changed Natural_join_column::table_name and db_name() to never return
NULL (used for print)
- thd->get_db() now returns db as a printable string (thd->db.str or "")
If compiling a non DBUG binary with
-DDBUG_ASSERT_AS_PRINTF asserts will be
changed to printf + stack trace (of stack
trace are enabled).
- Changed #ifndef DBUG_OFF to
#ifdef DBUG_ASSERT_EXISTS
for those DBUG_OFF that was just used to enable
assert
- Assert checking that could greatly impact
performance where changed to DBUG_ASSERT_SLOW which
is not affected by DBUG_ASSERT_AS_PRINTF
- Added one extra option to my_print_stacktrace() to
get more silent in case of stack trace printing as
part of assert.
IB: Fixes in logic when to do versioned or usual row updates. Now it is
able to do unversioned updates for versioned tables just by disabling
`TABLE_SHARE::versioned` flag.
SQL: DDL tracking for:
* RENAME TABLE, ALTER TABLE .. RENAME TO;
* DROP TABLE;
* data-modifying operations (f.ex. ALTER TABLE .. ADD/DROP COLUMN).
- SETVAL(sequence_name, next_value, is_used, round)
- ALTER SEQUENCE, including RESTART WITH
Other things:
- Added handler::extra() option HA_EXTRA_PREPARE_FOR_ALTER_TABLE to signal
ha_sequence() that it should allow write_row statments.
- ALTER ONLINE TABLE now works with SEQUENCE:s
