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https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning-monitoring.html
This section builds on the performance tuning advice from Section 17.9.1.3, “Tuning Compression for InnoDB Tables”, and shows how to find problems that might not turn up during initial testing. To dig deeper into performance considerations for ... Overall application performance, CPU and I/O utilization and the size of disk files are good indicators of how effective compression is for your ...
https://dev.mysql.com/doc/refman/8.4/en/join.html
MySQL supports the following JOIN syntax for the table_references part of SELECT statements and multiple-table DELETE and UPDATE statements: table_references: escaped_table_reference [, escaped_table_reference] ... A table reference (when it refers ...index_hint: { USE {INDEX|KEY} [FOR {JOIN|ORDER BY|GROUP BY}] ([index_list]) | {IGNORE|FORCE} {INDEX|KEY} [FOR {JOIN|ORDER BY|GROUP BY}] (index_list) } index_list: index_name [, index_name] ...
https://dev.mysql.com/doc/refman/8.4/en/select.html
You cannot use FOR UPDATE as part of the SELECT in a statement such as CREATE TABLE new_table SELECT ... (If you attempt to do so, the statement is rejected with the error Can't update table 'old_table' while 'new_table' is being created.) FOR SHARE ...[into_option] [FROM table_references [PARTITION partition_list]] [WHERE where_condition] [GROUP BY [ {col_name | expr | position}, ... SELECT [ALL | DISTINCT | DISTINCTROW ] [HIGH_PRIORITY] ...
https://dev.mysql.com/doc/heatwave/en/mys-hwgenai-ml-embed-table.html
Note In versions older than MySQL 9.2.1, to alter an existing table or create a new table, MySQL requires you to set the sql-require-primary-key system variable to 0. If the specified output table doesn't exist, then a new table is created. The ...
https://dev.mysql.com/doc/refman/8.4/en/sys-table-exists.html
Tests whether a given table exists as a regular table, a TEMPORARY table, or a view. If both a temporary and a permanent table exist with the given name, TEMPORARY is returned. Parameters in_db VARCHAR(64): The name of the database in which to ...
https://dev.mysql.com/doc/refman/8.4/en/mysqlshow.html
The mysqlshow client can be used to quickly see which databases exist, their tables, or a table's columns or indexes. If no table is given, all matching tables in the database are shown. If no column is given, all matching columns and column types ...The same information can be obtained by using those statements ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam-bulk-data-loading.html
For a MyISAM table, you can use concurrent inserts to add rows at the same time that SELECT statements are running, if there are no deleted rows in middle of the data file. With some extra work, it is possible to make LOAD DATA run even faster for a ... These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/doc/refman/8.4/en/metadata-locking.html
Metadata locking applies not just to tables, but also to schemas, stored programs (procedures, functions, triggers, scheduled events), tablespaces, user locks acquired with the GET_LOCK() function (see Section 14.14, “Locking Functions”), and ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-tablestatistics-category.html
Lists the Sys Schema Table Statistics metrics and provides a brief description of each. Table 6.42 Sys Schema Table Statistics Metrics NameDescriptionDelete Latency The total wait time of timed delete IO events for the table. Fetch Latency The ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-introduction.html
If you wish to make such information hidden from queries that select from these tables, you can do so by setting the value of the show_gipk_in_create_table_and_information_schema server system variable to OFF. INFORMATION_SCHEMA provides access to ...Other terms that are sometimes used for this information are data dictionary and system ...