instrument table->record[0], table->record[1] and share->default_values.
One should not access record image beyond share->reclength, even
if table->record[0] has some unused space after it (functions that
work with records, might get a copy of the record as an argument,
and that copy - not being record[0] - might not have this buffer space
at the end). See b80fa4000d and 444587d8a3
TRASH was mapped to TRASH_FREE and was supposed to be used for memory
that should not be accessed anymore, while TRASH_ALLOC() is to be
used for uninitialized but to-be-used memory.
But sometimes TRASH() was used in the latter sense.
Remove TRASH() macro, always use explicit TRASH_ALLOC() or TRASH_FREE().
and the system_versioning_transaction_registry variable.
The user enables transaction registry by specifying BIGINT for
row_start/row_end columns.
check mysql.transaction_registry structure on the first open,
not on startup. Avoid warnings unless transaction_registry
is actually used.
trx_undo_page_report_modify(): For SPATIAL INDEX, keep logging
updated off-page columns twice, so that
the minimum bounding rectangle (MBR) will be logged.
Avoiding the redundant logging would require larger changes
to the undo log format.
row_build_index_entry_low(): Handle SPATIAL_UNKNOWN more robustly,
by refusing to purge the record from the spatial index.
We can get this code when processing old undo log from 10.2.10 or
10.2.11 (the releases affected by MDEV-14799, which was a regression
from MDEV-14051).
If translation table present when we materialize the derived table then
change it to point to the materialized table.
Added debug info to see really what happens with what derived.
Other changes done to get this to work:
- Added 'internal_tables' to TABLE object to list which sequence tables
is needed to use the table.
- Mark any expression using DEFAULT() with LEX->default_used.
This is needed when deciding if we should open internal sequence
tables when a table is opened (we don't need to open sequence tables
if the main table is only used with SELECT).
- Create_and_open_temporary_table() can now also open all internal
sequence tables.
- Added option MYSQL_LOCK_USE_MALLOC to mysql_lock_tables()
to force memory allocation to be used with malloc instead of
memroot.
- Added flag to MYSQL_LOCK to remember if allocation was done with
malloc or memroot (makes code simpler and safer).
- init_one_table_for_prelocking() now takes argument for what lock to
use instead of it's a routine or something else.
- Renamed prelocking placeholders to make them more understandable as
they are now used in more code.
- Changed test in check_lock_and_start_stmt() if found table has correct
locks. The old test didn't work for tables that has lock
TL_WRITE_ALLOW_WRITE, which is what sequence tables are using.
- Added VCOL_NOT_VIRTUAL option to ensure that sequence functions can't
be used with virtual columns
- More sequence tests
Merge branch '10.3' into trunk
Both field_visibility and VERS_HIDDEN_FLAG exist independently.
TODO:
VERS_HIDDEN_FLAG should be replaced with SYSTEM_INVISIBLE (or COMPLETELY_INVISIBLE?).
Feature Definition:-
This feature adds invisible column functionality to server.
There is 4 level of "invisibility":
1. Not invisible (NOT_INVISIBLE) — Normal columns created by the user
2. A little bit invisible (USER_DEFINED_INVISIBLE) — columns that the
user has marked invisible. They aren't shown in SELECT * and they
don't require values in INSERT table VALUE (...). Otherwise
they behave as normal columns.
3. More invisible (SYSTEM_INVISIBLE) — Can be queried explicitly,
otherwise invisible from everything. Think ROWID sytem column.
Because they're invisible from ALTER TABLE and from CREATE TABLE
they cannot be created or dropped, they're created by the system.
User cant not create a column name which is same as of
SYSTEM_INVISIBLE.
4. Very invisible (COMPLETELY_INVISIBLE) — as above, but cannot be
queried either. They can only show up in EXPLAIN EXTENDED (might
be possible for a very invisible indexed virtual column) but
otherwise they don't exist for the user.If user creates a columns
which has same name as of COMPLETELY_INVISIBLE then
COMPLETELY_INVISIBLE column is renamed again. So it is completely
invisible from user.
Invisible Index(HA_INVISIBLE_KEY):-
Creation of invisible columns require a new type of index which
will be only visible to system. User cant see/alter/create/delete
this index. If user creates a index which is same name as of
invisible index then it will be renamed.
Syntax Details:-
Only USER_DEFINED_INVISIBLE column can be created by user. This
can be created by adding INVISIBLE suffix after column definition.
Create table t1( a int invisible, b int);
Rules:-
There are some rules/restrictions related to use of invisible columns
1. All the columns in table cant be invisible.
Create table t1(a int invisible); \\error
Create table t1(a int invisible, b int invisble); \\error
2. If you want invisible column to be NOT NULL then you have to supply
Default value for the column.
Create table t1(a int, b int not null); \\error
3. If you create a view/create table with select * then this wont copy
invisible fields. So newly created view/table wont have any invisible
columns.
Create table t2 as select * from t1;//t2 wont have t1 invisible column
Create view v1 as select * from t1;//v1 wont have t1 invisible column
4. Invisibility wont be forwarded to next table in any case of create
table/view as select */(a,b,c) from table.
Create table t2 as select a,b,c from t1; // t2 will have t1 invisible
// column(b), but this wont be invisible in t2
Create view v1 as select a,b,c from t1; // v1 will have t1 invisible
// column(b), but this wont be invisible in v1
Implementation Details:-
Parsing:- INVISIBLE_SYM is added into vcol_attribute(so its like unique
suffix), It is also added into keyword_sp_not_data_type so that table
can have column with name invisible.
Implementation detail is given by each modified function/created function.
(Some function are left as they were self explanatory)
(m= Modified, n= Newly Created)
mysql_prepare_create_table(m):- Extra checks for invisible columns are
added. Also some DEBUG_EXECUTE_IF are also added for test cases.
mysql_prepare_alter_table(m):- Now this will drop all the
COMPLETELY_INVISIBLE column and HA_INVISIBLE_KEY index. Further
Modifications are made to stop drop/change/delete of SYSTEM_INVISIBLE
column.
build_frm_image(m):- Now this allows incorporating field_visibility
status into frm image. To remain compatible with old frms
field_visibility info will be only written when any of the field is
not NOT_INVISIBLE.
extra2_write_additional_field_properties(n):- This will write field
visibility info into buffer. We first write EXTRA2_FIELD_FLAGS into
buffer/frm , then each next char will have field_visibility for each
field.
init_from_binary_frm_image(m):- Now if we get EXTRA2_FIELD_FLAGS,
then we will read the next n(n= number of fields) chars and set the
field_visibility. We also increment
thd->status_var.feature_invisible_columns. One important thing to
note if we find out that key contains a field whose visibility is
> USER_DEFINED_INVISIBLE then , we declare this key as invisible
key.
sql_show.cc is changed accordingly to make show table, show keys
correct.
mysql_insert(m):- If we get to know that we are doing insert in
this way insert into t1 values(1,1); without explicitly specifying
columns, then we check for if we have invisible fields if yes then
we reset the whole record, Why ? Because first we want hidden columns
to get default/null value. Second thing auto_increment has property
no default and no null which voilates invisible key rule 2, And
because of this it was giving error. Reseting table->record[0]
eliminates this issue. More info put breakpoint on handler::write_row
and see auto_increment value.
fill_record(m):- we continue loop if we find invisible column because
this is already reseted/will get its value if it is default.
Test cases:- Since we can not directly add > USER_DEFINED_INVISIBLE
column then I have debug_dbug to create it in mysql_prepare_create_table.
Patch Credit:- Serg Golubchik
IS DROPPED
ANALYSIS:
=========
It is advised not to tamper with the system tables.
When primary key is dropped from a system table, certain
operations on the table which tries to access the table key
information may lead to server exit.
FIX:
====
An appropriate error is now reported in such a case.
Add support for direct update and direct delete requests for spider.
A direct update/delete request handles all qualified rows in a single
operation rather than one row at a time.
Contains Spiral patches:
006_mariadb-10.2.0.direct_update_rows.diff MDEV-7704
008_mariadb-10.2.0.partition_direct_update.diff MDEV-7706
010_mariadb-10.2.0.direct_update_rows2.diff MDEV-7708
011_mariadb-10.2.0.aggregate.diff MDEV-7709
027_mariadb-10.2.0.force_bulk_update.diff MDEV-7724
061_mariadb-10.2.0.mariadb-10.1.8.diff MDEV-12870
- The differences compared to the original patches:
- Most of the parameters of the new functions are unnecessary. The
unnecessary parameters have been removed.
- Changed bit positions for new handler flags upon consideration of
handler flags not needed by other Spiral patches and handler flags
merged from MySQL.
- Added info_push() (Was originally part of bulk access patch)
- Didn't include code related to handler socket
- Added HA_CAN_DIRECT_UPDATE_AND_DELETE
Original author: Kentoku SHIBA
First reviewer: Jacob Mathew
Second reviewer: Michael Widenius
For BIT field null_bit is not set to 0 even for a field defined as NOT NULL.
So now in the function TABLE::create_key_part_by_field, if the bit field is not nullable
then the null_bit is explicitly set to 0
From comment in unreg.h:
Types of values in the MariaDB extra2 frm segment.
Each value is written as
type: 1 byte
length: 1 byte (1..255) or \0 and 2 bytes.
binary value of the 'length' bytes.
length == 1 is valid.
THD::vers_update_trt, trx_t::vers_update_trt, trx_savept_t::vers_update_trt:
Remove. Instead, determine from trx_t::mod_tables whether versioned
columns were affected by the transaction.
handlerton::prepare_commit_versioned: Replaces vers_get_trt_data.
Return the transaction start ID and also the commit ID, in case
the transaction modified any system-versioned columns (0 if not).
TR_table::store_data(): Remove (merge with update() below).
TR_table::update(): Add the parameters start_id, end_id.
ha_commit_trans(): Remove a condition on SQLCOM_ALTER_TABLE.
If we need something special for ALTER TABLE...ALGORITHM=INPLACE,
that can be done inside InnoDB by modifying trx_t::mod_tables.
innodb_prepare_commit_versioned(): Renamed from innodb_get_trt_data().
Check trx_t::mod_tables to see if any changes to versioned columns
are present.
trx_mod_table_time_t: A pair of logical timestamps, replacing the
undo_no_t in trx_mod_tables_t. Keep track of not only the first
modification to a persistent table in each transaction, but also
the first modification of a versioned column in a table.
dtype_t, dict_col_t: Add the accessor is_any_versioned(), to check
if the type refers to a system-versioned user or system column.
upd_t::affects_versioned(): Check if an update affects a versioned
column.
trx_undo_report_row_operation(): If a versioned column is affected
by the update, invoke trx_mod_table_time_t::set_versioned().
trx_rollback_to_savepoint_low(): If all changes to versioned columns
were rolled back, invoke trx_mod_table_time_t::rollback_versioned(),
so that trx_mod_table_time_t::is_versioned() will no longer hold.
TODO:
- Make get_thd_memroot() inline
- To do this, we need to reduce dependence of include files, especially
so that sql_class.h is not depending in item.h