Field_blob::store() has special code for GROUP_CONCAT temporary table
(to store blob values in Blob_mem_storage - this prevents them
from being freed/overwritten when a next row is read).
Field_geom and Field_blob_compressed inherit from Field_blob but they
have their own ::store() method without this special Blob_mem_storage
support.
Considering that non-grouping CONCAT() of such fields converts
them to plain BLOB, let's do the same for GROUP_CONCAT. To do it,
Item_func_group_concat::setup will signal that it's creating
a temporary table for GROUP_CONCAT, and Field_blog::make_new_field()
override will create base Field_blob when under group concat.
Field_string::val_int(), Field_string::val_real(), Field_string::val_decimal()
passed the whole buffer of field_length bytes to data type conversion routines.
This made conversion routines to print redundant trailing spaces in case of warnings.
Adding a method Field_string::to_lex_cstring() and using it inside
val_int(), val_real(), val_decimal(), val_str().
After this change conversion routines get the same value with what val_str() returns,
and no redundant trailing spaces are displayed.
This patch fixes the issue with passing the DEFAULT or IGNORE values to
positional parameters for some kind of SQL statements to be executed
as prepared statements.
The main idea of the patch is to associate an actual value being passed
by the USING clause with the positional parameter represented by
the Item_param class. Such association must be performed on execution of
UPDATE statement in PS/SP mode. Other corner cases that results in
server crash is on handling CREATE TABLE when positional parameter
placed after the DEFAULT clause or CALL statement and passing either
the value DEFAULT or IGNORE as an actual value for the positional parameter.
This case is fixed by checking whether an error is set in diagnostics
area at the function pack_vcols() on return from the function pack_expression()
use the original, not the truncated, field in the long unique prefix,
that is, in the hash(left(field, length)) expression.
because MyISAM CHECK/REPAIR in compute_vcols() moves table->field
but not prefix fields from keyparts.
Also, implement Field_string::cmp_prefix() for prefix comparison
of CHAR columns to work.
1. fix useless correction of dec_arg *after it was used*
2. use DECIMAL_NOT_SPECIFIED instead of NOT_FIXED_DEC, because the latter
is defined conditionally and has a wrong value in plugins
Index values for row_start/row_end was wrongly calculated for inplace
ALTER for some layout of virtual fields.
Possible impact
1. history row is not detected upon build clustered index for
inplace ALTER which may lead to duplicate key errors on
auto-increment and FTS index add.
2. foreign key constraint may falsely fail.
3. after inplace ALTER before server restart trx-based system
versioning can cause server crash or incorrect data written upon
UPDATE.
There where several reasons why the test failed:
- Constructors for Field_double and Field_float changed an argument
to the constructor instead of a the correct class variable.
- gcc 7.5.0 produced wrong code when inlining Field_double constructor
into Field_test_double constructor.
Fixed by changing the correct class variable and make the constructors
not inline to go around the gcc bug.
- Adding a new argument "flag" to MY_COLLATION_HANDLER::strnncollsp_nchars()
and a flag MY_STRNNCOLLSP_NCHARS_EMULATE_TRIMMED_TRAILING_SPACES.
The flag defines if strnncollsp_nchars() should emulate trailing spaces
which were possibly trimmed earlier (e.g. in InnoDB CHAR compression).
This is important for NOPAD collations.
For example, with this input:
- str1= 'a ' (Latin letter a followed by one space)
- str2= 'a ' (Latin letter a followed by two spaces)
- nchars= 3
if the flag is given, strnncollsp_nchars() will virtually restore
one trailing space to str1 up to nchars (3) characters and compare two
strings as equal:
- str1= 'a ' (one extra trailing space emulated)
- str2= 'a ' (as is)
If the flag is not given, strnncollsp_nchars() does not add trailing
virtual spaces, so in case of a NOPAD collation, str1 will be compared
as less than str2 because it is shorter.
- Field_string::cmp_prefix() now passes the new flag.
Field_varstring::cmp_prefix() and Field_blob::cmp_prefix() do
not pass the new flag.
- The branch in cmp_whole_field() in storage/innobase/rem/rem0cmp.cc
(which handles the CHAR data type) now also passed the new flag.
- Fixing UCA collations to respect the new flag.
Other collations are possibly also affected, however
I had no success in making an SQL script demonstrating the problem.
Other collations will be extended to respect this flags in a separate
patch later.
- Changing the meaning of the last parameter of Field::cmp_prefix()
from "number of bytes" (internal length)
to "number of characters" (user visible length).
The code calling cmp_prefix() from handler.cc was wrong.
After this change, the call in handler.cc became correct.
The code calling cmp_prefix() from key_rec_cmp() in key.cc
was adjusted according to this change.
- Old strnncollsp_nchar() related tests in unittest/strings/strings-t.c
now pass the new flag.
A few new tests also were added, without the flag.
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".
rename to stress that is a specific hack for Item_func_nextval
and should not be used for other items.
If a vcol uses Item_func_nextval, a corresponding table for the sequence
should be added to the prelocking list (in that sense NEXTVAL is not
simply a function, but more like a subquery), see add_internal_tables()
in DML_prelocking_strategy::handle_table(). At the moment it is only
implemented for DEFAULT, not for GENERATED ALWAYS AS, thus the
VCOL_NEXTVAL hack.
The ALTER related code cannot do at the same time both:
- modify partitions
- change column data types
Explicit changing of a column data type together with a partition change is
prohibited by the parter, so this is not allowed and returns a syntax error:
ALTER TABLE t MODIFY ts BIGINT, DROP PARTITION p1;
This fix additionally disables implicit data type upgrade
(e.g. from "MariaDB 5.3 TIME" to "MySQL 5.6 TIME", or the other way
around according to the current mysql56_temporal_format) in case of
an ALTER modifying partitions, e.g.:
ALTER TABLE t DROP PARTITION p1;
In such commands now only the partition change happens, while
the data types stay unchanged.
One can additionally run:
ALTER TABLE t FORCE;
either before or after the ALTER modifying partitions to
upgrade data types according to mysql56_temporal_format.
10.5 part: test cases and comments.
The code is in the merge commit 74fe1c44aa
When f.ex. table is partitioned by HASH(a) and we rename column `a' to
`b' partitioning filter stays unchanged: HASH(a). That's the wrong
behavior.
The patch updates partitioning filter in accordance to the new columns
names. That includes partition/subpartition expression and
partition/subpartition field list.
Not the SPIDER issue - happens to INSERT DELAYED.
the field::make_new_field does't copy the LONG_UNIQUE_HASH_FIELD
flag to the new field. Though the Delayed_insert::get_local_table
copies the field->vcol_info for this field. Ad a result
the parse_vcol_defs doesn't create the expression for that column
so the field->vcol_info->expr is NULL. Which leads to crash.
Backported fix for this from 10.5 - the flagg added in the
Delayed_insert::get_local_table.
Another problem with the USING HASH key is thst the
parse_vcol_defs modifies the table->keys content. Then the same
parse_vcol_defs is called on the table copy that has keys already
modified. Backported fix for that from 10.5 - key copying added
tot the Delayed_insert::get_local_table.
Finally - the created copy has to clear the expr_arena as
this table is not in the thd->open_tables list so won't be
cleared automatically.
Precision should be kept below DECIMAL_MAX_SCALE for computations.
It can be bigger in Item_decimal. I'd fix this too but it changes the
existing behaviour so problemmatic to ix.
column generated using date_format() and if()
vcol_info->expr is allocated on expr_arena at parsing stage. Since
expr item is allocated on expr_arena all its containee items must be
allocated on expr_arena too. Otherwise fix_session_expr() will
encounter prematurely freed item.
When table is reopened from cache vcol_info contains stale
expression. We refresh expression via TABLE::vcol_fix_exprs() but
first we must prepare a proper context (Vcol_expr_context) which meets
some requirements:
1. As noted above expr update must be done on expr_arena as there may
be new items created. It was a bug in fix_session_expr_for_read() and
was just not reproduced because of no second refix. Now refix is done
for more cases so it does reproduce. Tests affected: vcol.binlog
2. Also name resolution context must be narrowed to the single table.
Tested by: vcol.update main.default vcol.vcol_syntax gcol.gcol_bugfixes
3. sql_mode must be clean and not fail expr update.
sql_mode such as MODE_NO_BACKSLASH_ESCAPES, MODE_NO_ZERO_IN_DATE, etc
must not affect vcol expression update. If the table was created
successfully any further evaluation must not fail. Tests affected:
main.func_like
Reviewed by: Sergei Golubchik <serg@mariadb.org>
1. moved fix_vcol_exprs() call to open_table()
mysql_alter_table() doesn't do lock_tables() so it cannot win from
fix_vcol_exprs() from there. Tests affected: main.default_session
2. Vanilla cleanups and comments.
Hybrid functions (IF, COALESCE, etc) did not preserve the JSON property
from their arguments. The same problem was repeatable for single row subselects.
The problem happened because the method Item::is_json_type() was inconsistently
implemented across the Item hierarchy. For example, Item_hybrid_func
and Item_singlerow_subselect did not override is_json_type().
Solution:
- Removing Item::is_json_type()
- Implementing specific JSON type handlers:
Type_handler_string_json
Type_handler_varchar_json
Type_handler_tiny_blob_json
Type_handler_blob_json
Type_handler_medium_blob_json
Type_handler_long_blob_json
- Reusing the existing data type infrastructure to pass JSON
type handlers across all item types, including classes Item_hybrid_func
and Item_singlerow_subselect. Note, these two classes themselves do not
need any changes!
- Extending the data type infrastructure so data types can inherit
their properties (e.g. aggregation rules) from their base data types.
E.g. VARCHAR/JSON acts as VARCHAR, LONGTEXT/JSON acts as LONGTEXT
when mixed to a non-JSON data type. This is done by:
- adding virtual method Type_handler::type_handler_base()
- adding a helper class Type_handler_pair
- refactoring Type_handler_hybrid_field_type methods
aggregate_for_result(), aggregate_for_min_max(),
aggregate_for_num_op() to use Type_handler_pair.
This change also fixes:
MDEV-27361 Hybrid functions with JSON arguments do not send format metadata
Also, adding mtr tests for JSON replication. It was not covered yet.
And the current patch changes the replication code slightly.
Range optimizer incorrectly was used for ENUM columns
when the operation collation did not match the column collation.
Adding a virtual implementation of Field_enum::can_optimize_range()
which tests if the column and the operation collation match.
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.
