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https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlock-example.html
The following example illustrates how an error can occur when a lock request causes a deadlock. Client A enables innodb_print_all_deadlocks, creates two tables, 'Animals' and 'Birds', and inserts data into each. Thererfore, the previous read-only ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-disabling-tablespace-path-validation.html
At startup, InnoDB scans directories defined by the innodb_directories variable for tablespace files. The paths of discovered tablespace files are validated against the paths recorded in the data dictionary. If the paths do not match, the paths in ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-file-per-table-tablespaces.html
A file-per-table tablespace contains data and indexes for a single InnoDB table, and is stored on the file system in a single data file. File-per-table tablespace characteristics are described under the following topics in this section: ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-index-types.html
Each InnoDB table has a special index called the clustered index that stores row data. To get the best performance from queries, inserts, and other database operations, it is important to understand how InnoDB uses the clustered index to optimize ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-performance.html
Online DDL improves several aspects of MySQL operation: Applications that access the table are more responsive because queries and DML operations on the table can proceed while the DDL operation is in progress. Reduced locking and waiting for MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-page-compression.html
InnoDB supports page-level compression for tables that reside in file-per-table tablespaces. Page compression is enabled by specifying the COMPRESSION attribute with CREATE TABLE or ALTER TABLE. Supported Platforms Page compression requires sparse ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-optimizer-statistics.html
This section describes how to configure persistent and non-persistent optimizer statistics for InnoDB tables. Persistent optimizer statistics are persisted across server restarts, allowing for greater plan stability and more consistent query ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Optimizer statistics are not persisted to disk when innodb_stats_persistent=OFF or when individual tables are created or altered with STATS_PERSISTENT=0. Instead, statistics are stored in memory, and are lost when the server is shut down. Statistics ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-transaction-scheduling.html
InnoDB uses the Contention-Aware Transaction Scheduling (CATS) algorithm to prioritize transactions that are waiting for locks. When multiple transactions are waiting for a lock on the same object, the CATS algorithm determines which transaction ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-undo-tablespaces.html
Undo tablespaces contain undo logs, which are collections of records containing information about how to undo the latest change by a transaction to a clustered index record. Default undo tablespaces are created at initialization time to provide a ...