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https://dev.mysql.com/doc/refman/8.4/en/innodb-locking-reads.html
If you query data and then insert or update related data within the same transaction, the regular SELECT statement does not give enough protection. Other transactions can update or delete the same rows you just queried. InnoDB supports two types of ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-failure-conditions.html
The failure of an online DDL operation is typically due to one of the following conditions: An ALGORITHM clause specifies an algorithm that is not compatible with the particular type of DDL operation or storage engine. A LOCK clause specifies a low ...
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-performance-thread_concurrency.html
InnoDB uses operating system threads to process requests from user transactions. (Transactions may issue many requests to InnoDB before they commit or roll back.) On modern operating systems and servers with multi-core processors, where context ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-read-only-instance.html
You can query InnoDB tables where the MySQL data directory is on read-only media by enabling the --innodb-read-only configuration option at server startup. How to Enable To prepare an instance for read-only operation, make sure all the necessary ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-row-format.html
The row format of a table determines how its rows are physically stored, which in turn can affect the performance of queries and DML operations. As more rows fit into a single disk page, queries and index lookups can work faster, less cache memory ...
https://dev.mysql.com/doc/refman/8.4/en/insert-optimization.html
To optimize insert speed, combine many small operations into a single large operation. Ideally, you make a single connection, send the data for many new rows at once, and delay all index updates and consistency checking until the very end. The size ...
https://dev.mysql.com/doc/refman/8.4/en/internal-temporary-tables.html
In some cases, the server creates internal temporary tables while processing statements. The server creates temporary tables under conditions such as these: Evaluation of UNION statements, with some exceptions described later. Evaluation of some ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-indexes.html
MySQL supports invisible indexes; that is, indexes that are not used by the optimizer. The feature applies to indexes other than primary keys (either explicit or implicit). ALTER INDEX operation: ALTER TABLE t1 ALTER INDEX i_idx INVISIBLE; ALTER ...
https://dev.mysql.com/doc/refman/8.4/en/json-search-functions.html
The functions in this section perform search or comparison operations on JSON values to extract data from them, report whether data exists at a location within them, or report the path to data within them. JSON_CONTAINS(target, candidate[, path]) ...