Two new information_schema views are added:
* PERIOD table -- columns TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME,
PERIOD_NAME, START_COLUMN_NAME, END_COLUMN_NAME.
* KEY_PERIOD_USAGE -- works similar to KEY_COLUMN_USAGE, but for periods.
Columns CONSTRAINT_CATALOG, CONSTRAINT_SCHEMA, CONSTRAINT_NAME,
TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME, PERIOD_NAME
Two new columns are added to the COLUMNS view:
IS_SYSTEM_TIME_PERIOD_START, IS_SYSTEM_TIME_PERIOD_END - contain YES/NO.
This was done after discussions with Igor, Sanja and Bar.
The main reason for removing the deprication was to ensure that MariaDB
is always backward compatible whenever possible.
Other things:
- Added statistics counters, mainly for the feedback plugin.
- INTO OUTFILE
- INTO variable
- If INTO is using the old syntax (end of query)
First, we do not add VERS_UPDATE_UNVERSIONED_FLAG for system field and
that fixes SHOW CREATE result.
Second, we have to call check_sys_fields() for any CREATE TABLE and
there correct type is checked for system fields.
Third, we update system_time like as_row structures for ALTER TABLE
and that makes check_sys_fields() happy for ALTER TABLE when we make
system fields hidden.
versioning_fields flag indicates that any columns were specified WITH
SYSTEM VERSIONING. In that case we imply WITH SYSTEM VERSIONING for
the whole table and WITHOUT SYSTEM VERSIONING for the other columns.
- Remove row_start/row_end from keys in fix_create_like();
- Disable manual adding of implicit row_start/row_end to indexes on
CREATE TABLE. INVISIBLE_SYSTEM fields are unoperable by user;
- Fix memory leak on allocation of Key_part_spec.
Preparation for MDEV-16210:
replace.test:
key_type combinations: PK and UNIQUE.
foreign.test:
Preparation for key_type combinations.
Other fixes:
* Merged versioning.update2 into versioning.update;
* Removed test2 database and done individual drop instead.
1. Removed TIMESTAMP/TRANSACTION unit auto-detection in favor of default TIMESTAMP.
Reasons:
1.1. rare practical use and doubtful advantage of such auto-detection;
1.2. it conflicts with MDEV-16226 (TRX_ID-based versioned tables performance improvement).
Needless check_unit membership removed.
2. SQL: versioning type handling refactoring
Vers_type_handler hierarchy stores versioning properties of type.
virtual Type_handler::vers() accesses specialization of
Vers_type_handler for specific type.
virtual Vers_type_handler::kind() returns versioning kind
(timestamp/trx_id).
Removed Type_handler::Vers_history_point_check_unit() in favor of
Type_handler::vers().
Renames:
require_timestamp() -> require_timestamp_error()
require_trx_id() -> require_trx_id_error()
EDIT by Alexander Barkov (@abarkov):
check_sys_fields() moved to Vers_type_handler::check_sys_fields()
* do not allow versioned table to be without versioned (non-system) fields
* prohibit changing field versioning, when removing table versioning
* handle CREATE...SELECT as well
numerous fixes for CREATE ... SELECT with system versioning:
In CREATE ... SELECT the table is created based on the result set,
field properties do not count. That is
* field invisibility is *not* copied over
* AS ROW START/END is *not* copied over
* the history is *not* copied over
* system row_start/row_end fields can *not* be created from the SELECT part
