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https://dev.mysql.com/doc/refman/8.4/en/mysqld-safe.html
The actual locations are determined from the values configured into the distribution at the time it was built. mysqld_safe is the recommended way to start a mysqld server on Unix. mysqld_safe adds some safety features such as restarting the server ...
https://dev.mysql.com/doc/refman/8.4/en/mysqldump-copying-to-other-server.html
On Server 1: $> mysqldump db1 > dump.sql On Server 2: $> mysqladmin create db1 $> mysql db1 < dump.sql You can specify a different database name in this case, so omitting --databases from the mysqldump command enables you to dump data from one ...
https://dev.mysql.com/doc/refman/8.4/en/mysqlshow.html
* and ? characters are converted into SQL % and _ wildcard characters. The mysqlshow client can be used to quickly see which databases exist, their tables, or a table's columns or indexes. The same information can be obtained by using those ...
https://dev.mysql.com/doc/refman/8.4/en/null-values.html
The NULL value means “no data.” NULL can be written in any lettercase. Be aware that the NULL value is different from values such as 0 for numeric types or the empty string for string types. For text file import or export operations performed ...
https://dev.mysql.com/doc/refman/8.4/en/online-ddl-parallel-thread-configuration.html
The default setting is calculated by the number of available logical processors on the system divided by 8, with a minimum default value of 4. The maximum setting is 256, which is the maximum number for all sessions. The actual number of threads ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-blob.html
For a table with several columns, to reduce memory requirements for queries that do not use the BLOB column, consider splitting the BLOB column into a separate table and referencing it with a join query when needed. When storing a large blob ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-multi-tables.html
When the number of tables runs into the thousands or even millions, the overhead of dealing with all these tables becomes a new performance consideration. Some techniques for keeping individual queries fast involve splitting data across many tables.
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
This is needed when reading and parsing histograms from persistent storage into memory. The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-configuration-variables.html
Moving purge operations (a type of garbage collection) into a background thread. Different settings work best for servers with light, predictable loads, versus servers that are running near full capacity all the time, or that experience spikes of ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-many-tables.html
This step can take significant time on systems that partition the data into many tables. If you have configured non-persistent optimizer statistics (a non-default configuration), InnoDB computes index cardinality values for a table the first time ...