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https://dev.mysql.com/doc/refman/8.0/en/pluggable-storage-common-layer.html
Each storage engine generally has its own indexing methods, although some (such as B-tree indexes) are common to nearly all engines. A MySQL pluggable storage engine is the component in the MySQL database server that is responsible for performing ...
https://dev.mysql.com/doc/refman/8.0/en/analyze-table.html
For InnoDB tables, ANALYZE TABLE determines index cardinality by performing random dives on each of the index trees and updating index cardinality estimates accordingly. ANALYZE [NO_WRITE_TO_BINLOG | LOCAL] TABLE tbl_name UPDATE HISTOGRAM ON ...
https://dev.mysql.com/doc/refman/8.0/en/estimating-performance.html
For bigger tables, you can estimate that, using B-tree indexes, you need this many seeks to find a row: log(row_count) / log(index_block_length / 3 * 2 / (index_length + data_pointer_length)) + 1. In most cases, you can estimate query performance ...
https://dev.mysql.com/doc/refman/8.0/en/derived-condition-pushdown-optimization.html
MySQL 8.0.22 and later supports derived condition pushdown for eligible subqueries. When a derived table cannot be merged into the outer query (for example, if the derived table uses aggregation), pushing the outer WHERE condition down to the ...
https://dev.mysql.com/doc/refman/8.0/en/compressed-format.html
Compressed storage format is a read-only format that is generated with the myisampack tool. Compressed tables have the following characteristics: Compressed tables take very little disk space. This minimizes disk usage, which is helpful when using ...
https://dev.mysql.com/doc/refman/8.0/en/system-schema.html
innodb_dynamic_metadata: Used by the InnoDB storage engine to store fast-changing table metadata such as auto-increment counter values and index tree corruption flags. It contains tables that store information required by the MySQL server as it runs. A broad categorization is that the mysql schema contains data dictionary tables that store database object metadata, and system tables used for other operational ...
https://dev.mysql.com/doc/refman/8.0/en/table-scan-avoidance.html
You are comparing indexed columns with constant values and MySQL has calculated (based on the index tree) that the constants cover too large a part of the table and that a table scan would be faster. The output from EXPLAIN shows ALL in the type ...
https://dev.mysql.com/doc/refman/8.0/en/tracing-example.html
Now we can examine the trace, whose first column (QUERY), containing the original statement to be traced, is shown here: SELECT * FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE\G *************************** 1. row *************************** QUERY: SELECT ...
https://dev.mysql.com/doc/refman/8.0/en/linux-installation.html
The required script, mysql.server, can be found in the support-files directory under the MySQL installation directory or in a MySQL source tree. Linux supports a number of different solutions for installing MySQL. You can also use My Oracle Support ...
https://dev.mysql.com/doc/refman/8.0/en/myisamchk-other-options.html
--sort-index, -S Command-Line Format --sort-index Sort the index tree blocks in high-low order. myisamchk supports the following options for actions other than table checks and repairs: --analyze, -a Command-Line Format --analyze Analyze the ...