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B.3.3.5 Where MySQL Stores Temporary Files

https://dev.mysql.com/doc/refman/5.7/en/temporary-files.html

Some SELECT queries creates temporary SQL tables to hold intermediate results. On Unix, MySQL uses the value of the TMPDIR environment variable as the path name of the directory in which to store temporary files. If TMPDIR is not set, MySQL uses ...

B.3.6.2 TEMPORARY Table Problems

https://dev.mysql.com/doc/refman/5.7/en/temporary-table-problems.html

Temporary tables created with CREATE TEMPORARY TABLE have the following limitations: TEMPORARY tables are supported only by the InnoDB, MEMORY, MyISAM, and MERGE storage engines. Use ALTER TABLE instead: ALTER TABLE old_name RENAME new_name; You ...

8.14.2 Thread Command Values

https://dev.mysql.com/doc/refman/5.7/en/thread-commands.html

A thread can have any of the following Command values: Binlog Dump This is a thread on a replication source for sending binary log contents to a replica. Daemon This thread is internal to the server, not a thread that services a client connection.

8.14 Examining Server Thread (Process) Information

https://dev.mysql.com/doc/refman/5.7/en/thread-information.html

To ascertain what your MySQL server is doing, it can be helpful to examine the process list, which indicates the operations currently being performed by the set of threads executing within the server. row *************************** Id: 1 User: ...

5.5.3.1 Thread Pool Elements

https://dev.mysql.com/doc/refman/5.7/en/thread-pool-elements.html

MySQL Enterprise Thread Pool comprises these elements: A plugin library file implements a plugin for the thread pool code as well as several associated monitoring tables that provide information about thread pool operation. For a detailed ...

5.5.3.4 Thread Pool Tuning

https://dev.mysql.com/doc/refman/5.7/en/thread-pool-tuning.html

Assuming that the TP_THREAD_GROUP_STATS table is enabled, you can use the following query to determine the fraction of executed statements that stalled: SELECT SUM(STALLED_QUERIES_EXECUTED) / SUM(QUERIES_EXECUTED) FROM ... This section provides ...

8.15.11 Trace General Structure

https://dev.mysql.com/doc/refman/5.7/en/trace-general-structure.html

A trace follows the actual execution path very closely; for each join, there is a join preparation object, a join optimization object, and a join execution object. Query transformations (IN to EXISTS, outer join to inner join, and so on), ...

23.3.2 Trigger Metadata

https://dev.mysql.com/doc/refman/5.7/en/trigger-metadata.html

To obtain metadata about triggers: Query the TRIGGERS table of the INFORMATION_SCHEMA database.

8.2.4.2 Optimizing UPDATE Statements

https://dev.mysql.com/doc/refman/5.7/en/update-optimization.html

An update statement is optimized like a SELECT query with the additional overhead of a write. The speed of the write depends on the amount of data being updated and the number of indexes that are updated. Another way to get fast updates is to delay ...

6.4.3 The Password Validation Plugin

https://dev.mysql.com/doc/refman/5.7/en/validate-password.html

The validate_password plugin serves to improve security by requiring account passwords and enabling strength testing of potential passwords. This plugin exposes a set of system variables that enable you to configure password policy. The ...

Displaying 681 to 690 of 695 total results