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https://dev.mysql.com/doc/refman/8.4/en/optimizing-queries-myisam.html
If it is important to be able to do this, consider using the table in ways that avoid deleting rows. An update of the following form is very fast: UPDATE tbl_name SET count_col=count_col+1 WHERE key_col=constant; This is very important when you use ... Some general tips for speeding up queries on MyISAM tables: To help MySQL better optimize queries, use ANALYZE TABLE or run myisamchk --analyze on a table after it has been loaded with ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management-range-list.html
It is very important to remember that, when you drop a partition, you also delete all the data that was stored in that partition. However, there is one important difference in the effect this has on your use of the table afterward: You can no longer ... Adding and dropping of range and list partitions are handled in a similar fashion, so we discuss the management of both sorts of partitioning in this ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-pruning.html
Important Invalid DATE and DATETIME values referenced in the WHERE condition of a statement against a partitioned table are treated as NULL. Important This optimization is used only if the range size is smaller than the number of partitions. The ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-timing.html
To time wait events, the most important criterion is to reduce overhead, at the possible expense of the timer accuracy, so using the CYCLE timer is the best. To time statements, the most important criterion is to have an accurate measure, which is ... Events are collected by means of instrumentation added to the server source ...
https://dev.mysql.com/doc/refman/8.4/en/programs-overview.html
mysqlimport A client that imports text files into their respective tables using LOAD DATA. Later sections provide a more detailed description of each one, with the exception of NDB Cluster programs. Each program's description indicates its ...
https://dev.mysql.com/doc/refman/8.4/en/repair-table.html
Important Make a backup of a table before performing a table repair operation; under some circumstances the operation might cause data loss. Telling the server to ignore the .MYI file makes important table metadata stored in the .MYI unavailable to ...[QUICK] [EXTENDED] [USE_FRM] REPAIR TABLE repairs a possibly corrupted table, for certain storage engines ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-auto-increment.html
If it is important to have the same order on the source and replica, the rows must be ordered before assigning an AUTO_INCREMENT number. Statement-based replication of AUTO_INCREMENT, LAST_INSERT_ID(), and TIMESTAMP values is carried out subject to ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-differing-tables.html
Important Whether you use statement-based or row-based replication, the replica's copy of the table cannot contain more columns than the source's copy if you wish to employ attribute promotion. Important Replication between columns using different ... Source and target tables for replication do not have to be ...
https://dev.mysql.com/doc/refman/8.4/en/replication-options.html
auto.cnf has only a single [auto] section containing a single server_uuid setting and value; the file's contents appear similar to what is shown here: [auto] server_uuid=8a94f357-aab4-11df-86ab-c80aa9429562 Important The auto.cnf file is ... The ...
https://dev.mysql.com/doc/refman/8.4/en/replication-rules-db-options.html
Important A statement that is still permitted at this stage is not yet actually executed. Important For statement-based logging, an exception is made in the rules just given for the CREATE DATABASE, ALTER DATABASE, and DROP DATABASE statements.