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https://dev.mysql.com/doc/heatwave/en/mys-hw-lakehouse-export-query-results-json.html
As of MySQL 9.3.1, you can export the query results to a Newline-Delimited JSON (ND-JSON) file.
https://dev.mysql.com/doc/heatwave/en/mys-hw-lakehouse-export-query-results-Parquet.html
You can export query results to a Parquet file. ...
https://dev.mysql.com/doc/internals/en/traceable-queries.html
They are: SELECT; INSERT or REPLACE (with VALUES or SELECT); UPDATE/DELETE and their multi-table variants; all the previous ones prefixed by EXPLAIN; SET (unless it manipulates the optimizer_trace system variable); DO; DECLARE/CASE/IF/RETURN ...
https://dev.mysql.com/doc/refman/8.4/en/query-issues.html
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https://dev.mysql.com/doc/mysql-errors/8.4/en/server-error-reference.html
Error number: 1670; Symbol: ER_BINLOG_UNSAFE_SYSTEM_TABLE; SQLSTATE: HY000 Message: The statement is unsafe because it uses the general log, slow query log, or performance_schema table(s). Error number: 3550; Symbol: ER_IS_QUERY_INVALID_CLAUSE; ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/glossary.html
Performance monitoring involves checking whether queries that are slow or frequently run could be sped up or made less resource-intensive, by examining the EXPLAIN plan to check if the MySQL optimizer has chosen the most efficient ways to process ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbd-definition.html
Read queries which set locks also cause operation records to be created. When queries make use of the unique hash index, there are actually two operation records used per record in the transaction. (NDB 8.4.0) For queries using a unique hash index, ... The [ndbd] and [ndbd default] sections are used to configure the behavior of the cluster's data ...
https://dev.mysql.com/doc/refman/8.4/en/server-logs.html
You can control the general query and slow query logs during runtime. You can tell the server to write general query and slow query entries to log tables, log files, or both. For details, see Section 7.4.1, “Selecting General Query Log and Slow ...
https://dev.mysql.com/doc/refman/8.4/en/server-options.html
--log-raw Command-Line Format --log-raw[={OFF|ON}] System Variable log_raw Scope Global Dynamic Yes SET_VAR Hint Applies No Type Boolean Default Value OFF Passwords in certain statements written to the general query log, slow query log, and binary ... When you start the mysqld server, you can specify program options using any of the methods described in Section 6.2.2, “Specifying Program ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-optimization-with-exists.html
This is a problem because many real world subqueries become very slow unless the equality can be pushed down. For multiple-table subqueries, execution of NULL IN (SELECT ...) is particularly slow because the join optimizer does not optimize for the ...WHERE subquery_where) MySQL evaluates queries “from outside to inside.” That is, it first obtains the value of the outer expression outer_expr, and then runs the subquery and captures the rows that it ...