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https://dev.mysql.com/doc/refman/8.4/en/innodb-multi-versioning.html
However, if the index condition pushdown (ICP) optimization is enabled, and parts of the WHERE condition can be evaluated using only fields from the index, the MySQL server still pushes this part of the WHERE condition down to the storage engine ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/advanced.source.html
To fix a corruption problem in a replication source database, you can restore the backup, taking care not to propagate unnecessary SQL operations to the replica servers: Shut down the source database and then use, for example, the ...Pipe the ...
https://dev.mysql.com/doc/relnotes/connector-python/en/news-9-2-0.html
Functionality Added or Changed Bugs Fixed Functionality Added or Changed Added two new connection options: read_timeout (time limit to receive a response from the server) and write_timeout (time limit to send data to the server). These set the ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/meb-backup-optimistic.html
As the redo log files grow faster than they can be processed by mysqlbackup, the backup operation can actually fail when mysqlbackup cannot catch up with the redo log cycles and LSNs get overwritten by the server before they are read by mysqlbackup.
https://dev.mysql.com/doc/c-api/8.4/en/c-api-prepared-statement-type-conversions.html
Prepared statements transmit data between the client and server using C language variables on the client side that correspond to SQL values on the server side. If there is a mismatch between the C variable type on the client side and the ...The two ...The value represents a bit string that requires interpretation on the client ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-configuring-consistency-guarantees.html
Permitted Queries Under Consistency Rules Although all writes are held when using BEFORE_ON_PRIMARY_FAILOVER consistency level, not all reads are blocked to ensure that you can still inspect the server while it is applying backlog after a promotion ...This mode ensures that when a transaction is committed on the local member, any subsequent transaction reads the written value or a more recent value on any group ... Although the Transaction Synchronization Points section explains that conceptually there are two synchronization ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-diskio.html
If you follow best practices for database design and tuning techniques for SQL operations, but your database is still slow due to heavy disk I/O activity, consider these disk I/O optimizations. (Measure at a time when the server is not doing bulk ...Increase buffer pool size When table data is cached in the InnoDB buffer pool, it can be accessed repeatedly by queries without requiring any disk ...If the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlocks-handling.html
Use EXPLAIN SELECT to determine which indexes the MySQL server regards as the most appropriate for your queries. It explains how to organize database operations to minimize deadlocks and the subsequent error handling required in applications. This ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl.html
By default, MySQL performs the operation instantly or in place, as permitted, with as little locking as possible. The operation halts immediately if the requested level of concurrency is not available. To avoid tying up the server with an ALTER ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Configuring the Number of Sampled Pages The MySQL query optimizer uses estimated statistics about key distributions to choose the indexes for an execution plan, based on the relative selectivity of the index. Instead, statistics are stored in ...