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https://dev.mysql.com/doc/refman/8.4/en/foreign-key-optimization.html
If a table has many columns, and you query many different combinations of columns, it might be efficient to split the less-frequently used data into separate tables with a few columns each, and relate them back to the main table by duplicating the ...That way, each small table can have a primary key for fast lookups of its data, and you can query just the set of columns that you need using a join ...
https://dev.mysql.com/doc/refman/8.4/en/general-tablespaces.html
The unique file name is a 128 bit UUID formatted into five groups of hexadecimal numbers separated by dashes (aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee). A general tablespace is a shared InnoDB tablespace that is created using CREATE TABLESPACE syntax.
https://dev.mysql.com/doc/refman/8.4/en/generated-column-index-optimizations.html
The column is also indexed and the optimizer can take that index into account during execution plan construction. For example: CREATE TABLE t1 (f1 INT, gc INT AS (f1 + 1) STORED, INDEX (gc)); The generated column, gc, is defined as the expression f1 ...
https://dev.mysql.com/doc/refman/8.4/en/gis-polygon-property-functions.html
Such components are extracted and made into a single MultiPolygon, MultiLineString, or MultiPoint for centroid computation. Functions in this section return properties of Polygon or MultiPolygon values. Unless otherwise specified, functions in this ...
https://dev.mysql.com/doc/refman/8.4/en/group-by-functional-dependence.html
The following discussion provides several examples of the ways in which MySQL detects functional dependencies. The examples use this notation: {X} -> {Y} Understand this as “X uniquely determines Y,” which also means that Y is functionally ...
https://dev.mysql.com/doc/refman/8.4/en/group-by-modifiers.html
The GROUP BY clause permits a WITH ROLLUP modifier that causes summary output to include extra rows that represent higher-level (that is, super-aggregate) summary operations. ROLLUP thus enables you to answer questions at multiple levels of ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-deploying-locally.html
This - procedure assumes that MySQL Server was downloaded and unpacked - into the directory named mysql-8.4. The most common way to deploy Group Replication is using multiple server instances, to provide high availability. It is also possible to ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-flow-control.html
MySQL Group Replication ensures that a transaction commits only after a majority of the members in a group have received it and agreed on the relative order amongst all transactions sent concurrently. This approach works well if the total number of ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-observability.html
There is a lot of automation built into the Group Replication plugin. Nonetheless, you might sometimes need to understand what is happening behind the scenes. This is where the instrumentation of Group Replication and Performance Schema becomes ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-online-upgrade-combining-versions.html
Members take into account the entire major.minor.release version of the software when checking compatibility. Group Replication is versioned according to the MySQL Server version that the Group Replication plugin was bundled with. For example, if a ...