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https://dev.mysql.com/doc/refman/8.0/en/estimating-performance.html
For a 500,000-row table with a key value length of three bytes (the size of MEDIUMINT), the formula indicates log(500,000)/log(1024/3*2/(3+4)) + 1 = 4 seeks. To avoid this, increase the key cache size as the data grows. For small tables, you can ...
https://dev.mysql.com/doc/refman/8.0/en/index-page-merge-threshold.html
If the “page-full” percentage for an index page falls below the MERGE_THRESHOLD value when a row is deleted or when a row is shortened by an UPDATE operation, InnoDB attempts to merge the index page with a neighboring index page. row ...The ...
https://dev.mysql.com/doc/refman/8.0/en/subquery-materialization.html
Subquery materialization uses an in-memory temporary table when possible, falling back to on-disk storage if the table becomes too large. Either way, the row from t1 is not included in the query result. This indicates that, for a subquery that would ... The optimizer uses materialization to enable more efficient subquery ...
https://dev.mysql.com/doc/refman/8.0/en/replication-features-differing-tables.html
It is usually possible to replicate from a column of a given data type to another column of the same type and same size or width, where applicable, or larger. Row-based replication supports attribute promotion and demotion between smaller data types ...Attribute promotion can be used with both statement-based and row-based replication, and is not dependent on the storage engine used by either the source or the ...
https://dev.mysql.com/doc/refman/8.0/en/clone-plugin-options-variables.html
A larger buffer size may permit I/O device drivers to fetch data in parallel, which can improve cloning performance. clone_buffer_size Command-Line Format --clone-buffer-size System Variable clone_buffer_size Scope Global Dynamic Yes SET_VAR Hint ...
https://dev.mysql.com/doc/refman/8.0/en/fulltext-search-mecab.html
On supported Fedora, Debian and Ubuntu platforms (except Ubuntu 12.04 where the system mecab version is too old), MySQL dynamically links to the system mecab installation if it is installed to the default location. Also in the MySQL configuration ...
https://dev.mysql.com/doc/refman/8.0/en/optimizing-innodb-configuration-variables.html
Too much read-ahead can cause periodic drops in performance on a heavily loaded system. Adjusting log files to a size that makes sense for reliability and crash recovery. If you have kept your log files artificially small to avoid long startup ...
https://dev.mysql.com/doc/refman/8.0/en/precision-math.html
For example, you can treat a value that is too large for a column as an error rather than having the value truncated to lie within the range of the column's data type. MySQL provides support for precision math: numeric value handling that results ...
https://dev.mysql.com/doc/refman/8.0/en/source-installation-prerequisites.html
If you encounter build errors such as internal compiler error when compiling large source files, it may be that you have too little memory. Some of these tools are needed no matter whether you use a standard source distribution or a development ...
https://dev.mysql.com/doc/refman/8.0/en/sql-prepared-statements.html
Typically, database applications process large volumes of almost-identical statements, with only changes to literal or variable values in clauses such as WHERE for queries and deletes, SET for updates, and VALUES for inserts. To guard against too ...