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https://dev.mysql.com/doc/refman/8.4/en/innodb-standard-monitor.html
This limit does not apply to output written to server standard error output (stderr). Status This section shows the timestamp, the monitor name, and the number of seconds that per-second averages are based on. SEMAPHORES This section reports threads ... The Lock Monitor is the same as the Standard Monitor except that it includes additional lock ...
https://dev.mysql.com/doc/refman/8.4/en/is-null-optimization.html
For example, MySQL can use indexes and ranges to search for NULL with IS NULL. This optimization does not occur in cases when the column might produce NULL anyway (for example, if it comes from a table on the right side of a LEFT JOIN). This ...
https://dev.mysql.com/doc/refman/8.4/en/monitor-innodb-mutex-waits-performance-schema.html
For example, to disable InnoDB mutex wait event instruments related to full-text search, add the following rule: performance-schema-instrument='wait/synch/mutex/innodb/fts%=OFF' Note Rules with a longer prefix such as wait/synch/mutex/innodb/fts% ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-other-options.html
This improves join performance by enabling the join optimizer to better choose the order in which to join the tables and which indexes it should use. --block-search=offset, -b offset Command-Line Format --block-search=offset Type Numeric Find the ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-option-tables.html
ndb-connectstring: Address of NDB management server distributing configuration information for this cluster. ndb-default-column-format: Use this value (FIXED or DYNAMIC) by default for COLUMN_FORMAT and ROW_FORMAT options when creating or adding ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-table.html
To keep the index maintenance period to a reasonable time, set the innodb_ft_num_word_optimize option to specify how many words to update in the search index, and run a sequence of OPTIMIZE TABLE statements until the search index is fully updated.
https://dev.mysql.com/doc/refman/8.4/en/optimizer-features-to-trace.html
They are: Greedy search: With an N-table join, this could explore factorial(N) plans. These switches are listed here: greedy_search: Greedy search is not traced. dynamic_range: Only the first call to the range optimizer on this JOIN_TAB::SQL_SELECT ... Some features in the optimizer can be invoked many times during statement optimization and execution, and thus can make the trace grow beyond ...
https://dev.mysql.com/doc/refman/8.4/en/string-comparison-functions.html
To search for \, specify it as \\\\; this is because the backslashes are stripped once by the parser and again when the pattern match is made, leaving a single backslash to be matched against. This differs from comparisons performed with the = ...
https://dev.mysql.com/doc/refman/8.4/en/telemetry-metrics-meter-metrics.html
This includes only statements sent to the server by clients and not statements executed within stored programs. tc_log_page_waits Tc_log_page_waits ASYNC COUNTER For the memory-mapped implementation of the recovery log, this variable increments each ... The following server metrics are registered by default: mysql.stats Metrics mysql.stats.com Metrics mysql.stats.connection Metrics mysql.perf_schema Metrics mysql.stats.handler Metrics mysql.stats.myisam Metrics mysql.stats.ssl Metrics mysql.inno Metrics mysql.inno.buffer_pool Metrics mysql.inno.data Metrics mysql.x Metrics mysql.x.stmt Metrics The maximum number of metric instruments which can be created is set by ...
https://dev.mysql.com/doc/relnotes/mysql/8.4/en/news-8-4-6.html
(Bug #36524167) On MacOS, silenced deprecation warnings generated by Xcode 14; this includes suggestions to use snprintf(3) instead of sprintf(3), and warnings about possible loss of precision when converting from 64-bit to 32-bit integers. This ...