MySQL 4.1(en)

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8.2.2.2 Optimizing Subqueries with Materialization

https://dev.mysql.com/subquery-materialization.html

oe [NOT] IN (SELECT ie ...) The predicate is IN or NOT IN and a result of UNKNOWN (NULL) has the same meaning as a result of FALSE. The optimizer uses materialization to enable more efficient subquery processing. Materialization speeds up query ...

27.4.3.3 The host_summary_by_file_io_type and x$host_summary_by_file_io_type Views

https://dev.mysql.com/sys-host-summary-by-file-io-type.html

Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. These views summarize file I/O, grouped by host and event type. By default, ...

27.4.3.2 The host_summary_by_file_io and x$host_summary_by_file_io Views

https://dev.mysql.com/sys-host-summary-by-file-io.html

Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. By default, rows are sorted by descending total file I/O latency. The ...

27.4.3.4 The host_summary_by_stages and x$host_summary_by_stages Views

https://dev.mysql.com/sys-host-summary-by-stages.html

27.4.3.5 The host_summary_by_statement_latency and x$host_summary_by_statement_latency Views

https://dev.mysql.com/sys-host-summary-by-statement-latency.html

Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. The host_summary_by_statement_latency and x$host_summary_by_statement_latency ...

27.4.3.6 The host_summary_by_statement_type and x$host_summary_by_statement_type Views

https://dev.mysql.com/sys-host-summary-by-statement-type.html

Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. These views summarize informaion about statements executed, grouped by host ...

27.4.3.1 The host_summary and x$host_summary Views

https://dev.mysql.com/sys-host-summary.html

Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. These views summarize statement activity, file I/O, and connections, grouped ...

27.4.3.10 The io_by_thread_by_latency and x$io_by_thread_by_latency Views

https://dev.mysql.com/sys-io-by-thread-by-latency.html

These views summarize I/O consumers to display time waiting for I/O, grouped by thread. The io_by_thread_by_latency and x$io_by_thread_by_latency views have these columns: user For foreground threads, the account associated with the thread.

27.4.3.16 The memory_by_host_by_current_bytes and x$memory_by_host_by_current_bytes Views

https://dev.mysql.com/sys-memory-by-host-by-current-bytes.html

27.4.3.18 The memory_by_user_by_current_bytes and x$memory_by_user_by_current_bytes Views

https://dev.mysql.com/sys-memory-by-user-by-current-bytes.html

Rows for which the USER column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. By default, rows are sorted by descending amount of memory used. The ...

Displaying 531 to 540 of 565 total results

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Document created the 26/06/2006, last modified the 26/10/2018
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References

Manuel MySQL : https://dev.mysql.com/

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