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https://dev.mysql.com/doc/refman/8.4/en/partitioning-management-hash-key.html
Tables which are partitioned by hash or by key are very similar to one another with regard to making changes in a partitioning setup, and both differ in a number of ways from tables which have been partitioned by range or list. For that reason, ...
https://dev.mysql.com/doc/refman/8.4/en/charset-unicode-conversion.html
In terms of table content, conversion from utf8mb3 to utf8mb4 presents no problems: For a BMP character, utf8mb4 and utf8mb3 have identical storage characteristics: same code values, same encoding, same length. In terms of table structure, these are ... This section describes issues that you may face when converting character data between the utf8mb3 and utf8mb4 character ...
https://dev.mysql.com/doc/refman/8.4/en/engine-condition-pushdown-optimization.html
Joins are not directly supported; conditions involving multiple tables are pushed separately where possible. Previously, engine condition pushdown was limited to terms referring to column values from the same table to which the condition was being ... This optimization improves the efficiency of direct comparisons between a nonindexed column and a ...
https://dev.mysql.com/doc/refman/8.4/en/correlated-subqueries.html
A correlated subquery is a subquery that contains a reference to a table that also appears in the outer query. For example: SELECT * FROM t1 WHERE column1 = ANY (SELECT column1 FROM t2 WHERE t2.column2 = t1.column2); Notice that the subquery ...So, ...
https://dev.mysql.com/doc/refman/8.4/en/error-log-rule-based-filtering.html
The log_filter_dragnet log filter component enables log filtering based on user-defined rules. To enable the log_filter_dragnet filter, first load the filter component, then modify the log_error_services value. The following example enables ...
https://dev.mysql.com/doc/workbench/en/wb-eer-color-key.html
Color connection lines within EER diagrams provide quick visual information about how the tables in your model relate. The following table defines the meaning of each color and indicates how you can open the underlying table information from your ...Existing connection lines are highlighted when you use a pointer device to hover on different database ...
https://dev.mysql.com/doc/workbench/en/wb-relationship-tools.html
Typically this occurs where an intermediary table is created to resolve a many-to-many relationship. In such cases, the primary key is usually a composite key made up of the primary keys from the two original tables. A non-identifying relationship: ...Click on the appropriate tool for the type of relationship you wish to ...
https://dev.mysql.com/doc/refman/8.4/en/archive-storage-engine.html
The ARCHIVE storage engine produces special-purpose tables that store large amounts of unindexed data in a very small footprint. When you create an ARCHIVE table, the storage engine creates files with names that begin with the table name. The ...To ...
https://dev.mysql.com/doc/refman/8.4/en/bug-reports.html
If a database table is related to the problem, include the output from the SHOW CREATE TABLE db_name.tbl_name statement in the bug report. This is a very easy way to get the definition of any table in a database. You should also include the output ... Before posting a bug report about a problem, please try to verify that it is a bug and that it has not been reported already: Start by searching the MySQL online manual at ...
https://dev.mysql.com/doc/refman/8.4/en/condition-filtering.html
In join processing, prefix rows are those rows passed from one table in a join to the next. In general, the optimizer attempts to put tables with low prefix counts early in the join order to keep the number of row combinations from increasing ...