Long UNIQUE HASH index silently creates virtual column index, which should
be impossible for base columns featuring AUTO_INCREMENT.
Fix: add a relevant check; add new vcol type for a prettier error message.
In commit 1811fd51fb the assertion
should have said error_reported instead of !error_reported.
But, that revised assertion would still fail in main.defaults
where ER_BAD_DATA is reported during CREATE TABLE.
This is a duplicate of MDEV-18278 89936f11e9, but I will add an
additional assertion
Description:
The frm corruption should not be reported during CREATE TABLE. Normally
it doesn't, and the data to fill TABLE is taken by open_table_from_share
call. However, the vcol data is stored as SQL string in
table->s->vcol_defs.str and is anyway parsed on each table open.
It is impossible [or hard] to avoid, because it's hard to clone the
expression tree in general (it's easier to parse).
Normally parse_vcol_defs should only fail on semantic errors. If so,
error_reported is set to true. Any other failure is not expected during
table creation. There is either unhandled/unacknowledged error, or
something went really wrong, like memory reject. This all should be
asserted anyway.
Solution:
* Set *error_reported=true for the forward references check;
* Assert for every unacknowledged error during table creation.
There were two independent problems which lead to the crash
and to the non-relevant records returned in I_S queries:
- The code in the I_S implementation was not secure
about values with 0x00 bytes.
It's fixed by using check_db_name() and check_table_name()
inside make_table_name_list(), and by adding the test for
0x00 inside check_table_name().
- The code in Item_string::print() did not convert
strings without introducers when restoring
the CREATE VIEW statement from an Item tree.
This made wrong literals inside the "query" line in the view FRM file
in cases when the VIEW parse time
character_set_client!=character_set_connection.
That's fixed by adding a proper conversion.
This change also fixed a similar problem in SHOW PROCEDURE CODE -
the literals were displayed in wrong character set in SP instructions
in cases when the SP parse time
character_set_client!=character_set_connection.
Server crashes in Field::register_field_in_read_map upon select from
partitioned table with indexed by prefix virtual column.
After several read-mark fixes a problem has surfaced:
Since KEY (c(10),a) uses only a prefix of c, a new field is created,
duplicated from table->field[3], with a new length. However,
vcol_inco->expr is not copied.
Therefore, (*key_info)->key_part[i].field->vcol_info->expr was left NULL
in ha_partition::index_init().
Solution: copy vcol_info from table field when it's set up.
Server crashes in Field::register_field_in_read_map upon select from
partitioned table with indexed by prefix virtual column.
After several read-mark fixes a problem has surfaced:
Since KEY (c(10),a) uses only a prefix of c, a new field is created,
duplicated from table->field[3], with a new length. However,
vcol_inco->expr is not copied.
Therefore, (*key_info)->key_part[i].field->vcol_info->expr was left NULL
in ha_partition::index_init().
Solution: initialize vcols before key initialization
Also key initialization is moved to a function.
Reformulate mark_columns_used_by_index* function family in a more laconic
way:
mark_columns_used_by_index -> mark_index_columns
mark_columns_used_by_index_for_read_no_reset -> mark_index_columns_for_read
mark_columns_used_by_index_no_reset -> mark_index_columns_no_reset
static mark_index_columns -> do_mark_index_columns
Several different test cases were failing under the same reason: the
fields in a vcol expression were not marked during marking columns of a key
contatining virtual column for read.
Fix: make marking columns of a key for read a special case where
register_field_in_read_map() is done instead of plain bitmap_set_bit().
Some test cases are only reproducible in 10.4+, but the fix is applicable
to 10.2+
This is a 10.2+ part of a jira task
The two bugs regarding virtual column marking have been fixed:
1. UPDATE of a partitioned table, where the optimizer has chosen a
secondary index to make a filesort;
2. INSERT into a table with a nonblob field generated from a blob, with
binlog enabled and binlog_row_image=noblob.
3. DELETE from a view on a table with virtual column.
Generally the assertion happens from update_virtual_fields() call
These bugs are root-caused by missing field marking for dependant fields
of a virtual column.
Therefore a fix is: mark all the fields involved in the vcol expression by
calling field->register_field_in_read_map() instead just setting a single
bit.
3 was reproducible only on 10.4+, however the problem might has just been
invisible in the earlier versions. The fix is applicable to 10.2-10.3 as
well.
Problem:
The problem happened because of a conceptual flaw in the server code:
a. The table level CHARSET/COLLATE clause affected all data types,
including numeric and temporal ones:
CREATE TABLE t1 (a INT) CHARACTER SET utf8 [COLLATE utf8_general_ci];
In the above example, the Column_definition_attributes
(and then the FRM record) for the column "a" erroneously inherited
"utf8" as its character set.
b. The "ALTER TABLE t1 CONVERT TO CHARACTER SET csname" statement
also erroneously affected Column_definition_attributes::charset
for numeric and temporal data types and wrote "csname" as their
character set into FRM files.
So now we have arbitrary non-relevant charset ID values for numeric
and temporal data types in all FRM files in the world :)
The code in the server and the other engines did not seem to be affected
by this flaw. Only InnoDB inplace ALTER was affected.
Solution:
Fixing the code in the way that only character string data types
(CHAR,VARCHAR,TEXT,ENUM,SET):
- inherit the table level CHARSET/COLLATE clause
- get the charset value according to "CONVERT TO CHARACTER SET csname".
Numeric and temporal data types now always get &my_charset_numeric
in Column_definition_attributes::charset and always write its ID into FRM files:
- no matter what the table level CHARSET/COLLATE clause is, and
- no matter what "CONVERT TO CHARACTER SET" says.
Details:
1. Adding helper classes to pass small parts of HA_CREATE_INFO
into Type_handler methods:
- Column_derived_attributes - to pass table level CHARSET/COLLATE,
so columns that do not have explicit CHARSET/COLLATE clauses
can derive them from the table level, e.g.
CREATE TABLE t1 (a VARCHAR(1), b CHAR(1)) CHARACTER SET utf8;
- Column_bulk_alter_attributes - to pass bulk attribute changes
generated by the ALTER related code. These bulk changes affect
multiple columns at the same time:
ALTER TABLE ... CONVERT TO CHARACTER SET csname;
Note, passing the whole HA_CREATE_INFO directly to Type_handler
would not be good: HA_CREATE_INFO is huge and would need not desired
dependencies in sql_type.h and sql_type.cc. The Type_handler API should
use smallest possible data types!
2. Type_handler::Column_definition_prepare_stage1() is now responsible
to set Column_definition::charset properly, according to the data type,
for example:
- For string data types, Column_definition_attributes::charset is set from
the table level CHARSET/COLLATE clause (if not specified explicitly in
the column definition).
- For numeric and temporal fields, Column_definition_attributes::charset is
set to &my_charset_numeric, no matter what the table level
CHARSET/COLLATE says.
- For GEOMETRY, Column_definition_attributes::charset is set to
&my_charset_bin, no matter what the table level CHARSET/COLLATE says.
Previously this code (setting `charset`) was outside of of
Column_definition_prepare_stage1(), namely in
mysql_prepare_create_table(), and was erroneously called for
all data types.
3. Adding Type_handler::Column_definition_bulk_alter(), to handle
"ALTER TABLE .. CONVERT TO". Previously this code was inside
get_sql_field_charset() and was erroneously called for all data types.
4. Removing the Schema_specification_st parameter from
Type_handler::Column_definition_redefine_stage1().
Column_definition_attributes::charset is now fully properly initialized by
Column_definition_prepare_stage1(). So we don't need access to the
table level CHARSET/COLLATE clause in Column_definition_redefine_stage1()
any more.
5. Other changes:
- Removing global function get_sql_field_charset()
- Moving the part of the former get_sql_field_charset(), which was
responsible to inherit the table level CHARSET/COLLATE clause to
new methods:
-- Column_definition_attributes::explicit_or_derived_charset() and
-- Column_definition::prepare_charset_for_string().
This code is only needed for string data types.
Previously it was erroneously called for all data types.
- Moving another part, which was responsible to apply the
"CONVERT TO" clause, to
Type_handler_general_purpose_string::Column_definition_bulk_alter().
- Replacing the call for get_sql_field_charset() in sql_partition.cc
to sql_field->explicit_or_derived_charset() - it is perfectly enough.
The old code was redundant: get_sql_field_charset() was called from
sql_partition.cc only when there were no a "CONVERT TO CHARACTER SET"
clause involved, so its purpose was only to inherit the table
level CHARSET/COLLATE clause.
- Moving the code handling the BINCMP_FLAG flag from
mysql_prepare_create_table() to
Column_definition::prepare_charset_for_string():
This code is responsible to resolve the BINARY comparison style
into the corresponding _bin collation, to do the following transparent
rewrite:
CREATE TABLE t1 (a VARCHAR(10) BINARY) CHARSET utf8; ->
CREATE TABLE t1 (a VARCHAR(10) CHARACTER SET utf8 COLLATE utf8_bin);
This code is only needed for string data types.
Previously it was erroneously called for all data types.
6. Renaming Table_scope_and_contents_source_pod_st::table_charset
to alter_table_convert_to_charset, because the only purpose it's used for
is handlering "ALTER .. CONVERT". The new name is much more self-descriptive.
The issue happens when the secondary keys are extended with primary
key parts. Inside the function TABLE_SHARE::init_from_binary_frm_image()
adds the length bytes for the primary key key parts to the length of the
secondary key. This is not needed because when the extended keys are
used we recalculate the length for the used key parts.
Also removed TABLE_SHARE::total_key_length as it is not used in the code
Apporved-by: Monty <monty@mariadb.org>
The problem was that the server was calling virtual functions on a record
that was not initialized with new data.
This happened when fill_record() was aborted in the middle because an
error in save_val() or save_in_field()
Problem:
Queries like this showed performance degratation in 10.4 over 10.3:
SELECT temporal_literal FROM t1;
SELECT temporal_literal + 1 FROM t1;
SELECT COUNT(*) FROM t1 WHERE temporal_column = temporal_literal;
SELECT COUNT(*) FROM t1 WHERE temporal_column = string_literal;
Fix:
Replacing the universal member "MYSQL_TIME cached_time" in
Item_temporal_literal to data type specific containers:
- Date in Item_date_literal
- Time in Item_time_literal
- Datetime in Item_datetime_literal
This restores the performance, and make it even better in some cases.
See benchmark results in MDEV.
Also, this change makes futher separations of Date, Time, Datetime
from each other, which will make it possible not to derive them from
a too heavy (40 bytes) MYSQL_TIME, and replace them to smaller data
type specific containers.
* Allocate items on thd->mem_root while refixing vcol exprs
* Make vcol tree changes register and roll them back after the statement is executed.
Explanation:
Due to collation implementation specifics an Item tree could change while fixing.
The tricky thing here is to make it on a proper arena.
It's usually not a problem when a field is deterministic, however, makes a pain vice-versa, during allocation allocating.
A non-deterministic field should be refixed on each statement, since it depends on the environment state.
Changing the tree will be temporary and therefore it should be reverted after the statement execution.
Fix stale virtual field value in 4 cases: when virtual field depends
on row_start/row_end in timestamp/trx_id versioned table. row_start
dep is recalculated in vers_update_fields() (SQL and InnoDB
layer). row_end dep is recalculated on history row insert.
In AddressSanitizer, we only want memory poisoning to happen
in connection with custom memory allocation or freeing.
The primary use of MEM_UNDEFINED is for declaring memory uninitialized
in Valgrind or MemorySanitizer. We do not want MEM_UNDEFINED to
have the unwanted side effect that AddressSanitizer would no longer
be able to complain about accessing unallocated memory.
MEM_UNDEFINED(): Define as no-op for AddressSanitizer.
MEM_MAKE_ADDRESSABLE(): Define as MEM_UNDEFINED() or
ASAN_UNPOISON_MEMORY_REGION().
MEM_CHECK_ADDRESSABLE(): Wrap also __asan_region_is_poisoned().
- Some of the bug fixes are backports from 10.5!
- The fix in innobase/fil/fil0fil.cc is just a backport to get less
error messages in mysqld.1.err when running with valgrind.
- Renamed HAVE_valgrind_or_MSAN to HAVE_valgrind
- Removed not needed bzero in void TABLE::initialize_quick_structures().
- Replaced bzero with TRASH_ALLOC() to have this change verfied with
memory checkers
- Added missing table->quick_keys.is_set in table_cond_selectivity()
Make sure to initialize members of TABLE::reginfo when TABLE::init is called. In this case the problem
was that table->reginfo.join_tab was set for the SELECT query and then was reused by the UPDATE query.
This case occurred only when the SELECT query had a degenerate join.
Problem:- Calling mark_columns_per_binlog_row_image() earlier may change the
result of mark_virtual_columns_for_write() , Since it can set the bitmap on
for virtual column, and henceforth mark_virtual_column_deps(field) will
never be called in mark_virtual_column_with_deps.
This bug is not specific for long unique, It also fails for this case
create table t2(id int primary key, a blob, b varchar(20) as (LEFT(a,2)));