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.
Fix test cases to remove hardcoded expected number for 'handler_next_read'
status variable. Apparently, number of rows in I_S.routines depends on
whether or not 'sys' schema is loaded, and this depends on whether or not
perfschema is compiled in.
For queries like
"SELECT * FROM INFORMATION_SCHEMA.PARAMETERS
WHERE SPECIFIC_NAME='proc_name'"
and
"SELECT * FROM INFORMATION_SCHEMA.ROUTINES
WHERE ROUTINE_NAME='proc_name'"
there is a possibility to avoid loading of the stored procedure code
and parsing it to retrieve parameters.
If the name of the procedure/function is specified explicitly then
it is possible to filter out routines that do not match at
an early stage.
Queries to INFORMATION_SCHEMA.PARAMETERS and ROUTINES tables are always
performed using full index scan of the mysql.proc primary key
on fields (`db`,`name`,`type`). This can be done in a much more effective
way if `db` and `name` field values can be derived from the WHERE statement,
like here:
SELECT * FROM INFORMATION_SCHEMA.PARAMETERS
WHERE SPECIFIC_SCHEMA = 'test' AND SPECIFIC_NAME = 'my_func'
or here:
SELECT * FROM information_schema.ROUTINES
WHERE ROUTINE_SCHEMA='test' AND ROUTINE_NAME='my_func'.
In such cases index range scan may be employed instead of full index
scan. This commit makes the server retrieve lookup field values from
the SQL statement and perform index range scan instead of full index
scan if possible.
The 10.5 version of the patch.
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
