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https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-metrics-table.html
Create a simple InnoDB table: mysql> USE test; Database changed mysql> CREATE TABLE t1 (c1 INT) ENGINE=INNODB; Query OK, 0 rows affected (0.02 sec) Enable the dml_inserts counter. The INNODB_METRICS table provides information about InnoDB ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-failure-conditions.html
The tmpdir or innodb_tmpdir file system runs out of disk space, while MySQL writes temporary sort files on disk during index creation. For example, you might insert duplicate values into a column while a unique index is being created, or you might ... The failure of an online DDL operation is typically due to one of the following conditions: An ALGORITHM clause specifies an algorithm that is not compatible with the particular type of DDL operation or storage ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-restrictions-limitations.html
You cannot create a table with a column name that matches the name of an internal InnoDB column (including DB_ROW_ID, DB_TRX_ID, and DB_ROLL_PTR. mysql> CREATE TABLE t1 (c1 INT, db_row_id INT) ENGINE=INNODB; ERROR 1166 (42000): Incorrect column name ... This section describes restrictions and limitations of the InnoDB storage ...
https://dev.mysql.com/doc/refman/8.4/en/insert-on-duplicate.html
If you specify an ON DUPLICATE KEY UPDATE clause and a row to be inserted would cause a duplicate value in a UNIQUE index or PRIMARY KEY, an UPDATE of the old row occurs. If column b is also unique, the INSERT is equivalent to this UPDATE statement ...
https://dev.mysql.com/doc/refman/8.4/en/insert-select.html
When selecting from and inserting into the same table, MySQL creates an internal temporary table to hold the rows from the SELECT and then inserts those rows into the target table. To ensure that the binary log can be used to re-create the original ... INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name [, col_name] ...)] { SELECT ...
https://dev.mysql.com/doc/refman/8.4/en/insert.html
If both the column list and the VALUES list are empty, INSERT creates a row with each column set to its default value: INSERT INTO tbl_name () VALUES(); If strict mode is not enabled, MySQL uses the implicit default value for any column that has no ... INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name [, col_name] ...)] { {VALUES | VALUE} (value_list) [, (value_list)] ...
https://dev.mysql.com/doc/refman/8.4/en/json-function-reference.html
Table 14.22 JSON Functions Name Description Deprecated -> Return value from JSON column after evaluating path; equivalent to JSON_EXTRACT(). ->> Return value from JSON column after evaluating path and unquoting the result; equivalent to ...
https://dev.mysql.com/doc/refman/8.4/en/key-cache-restructuring.html
For example: mysql> SET GLOBAL cold_cache.key_buffer_size=4*1024*1024; If you assign to either the key_buffer_size or key_cache_block_size key cache component a value that differs from the component's current value, the server destroys the cache's ... A key cache can be restructured at any time by updating its parameter ...
https://dev.mysql.com/doc/refman/8.4/en/multiple-key-caches.html
By default, table indexes are assigned to the main (default) key cache created at the server startup. Note As of MySQL 8.4, the compound-part structured-variable syntax discussed here for referring to multiple MyISAM key caches is deprecated.
https://dev.mysql.com/doc/refman/8.4/en/multiple-windows-services.html
On Windows, a MySQL server can run as a Windows service. The procedures for installing, controlling, and removing a single MySQL service are described in Section 2.3.3.8, “Starting MySQL as a Windows Service”. To set up multiple MySQL services, ...