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https://dev.mysql.com/doc/refman/8.4/en/partitioning-info.html
When insertions, deletions, or updates are made to partitioned tables, the binary log records information about the partition and (if any) the subpartition in which the row event took place. This section discusses obtaining information about ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-pruning.html
An INSERT statement also accesses only one partition per inserted row; this is true even for a table that is partitioned by HASH or KEY although this is not currently shown in the output of EXPLAIN. The optimization known as partition pruning is ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-range.html
A table that is partitioned by range is partitioned in such a way that each partition contains rows for which the partitioning expression value lies within a given range. Ranges should be contiguous but not overlapping, and are defined using the ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-types.html
With this type of partitioning, a partition is selected based on the value returned by a user-defined expression that operates on column values in rows to be inserted into the table. When a new row is inserted into a partitioned table, it is these ... This section discusses the types of partitioning which are available in MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-naming.html
For example, an insert might activate a trigger that causes an update. An instrument name consists of a sequence of elements separated by '/' characters. Example names: wait/io/file/myisam/log wait/io/file/mysys/charset wait/lock/table/sql/handler ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-metadata-locks-table.html
When a metadata lock is requested and not obtained immediately, a row with a status of PENDING is inserted. MySQL uses metadata locking to manage concurrent access to database objects and to ensure data consistency; see Section 10.11.4, “Metadata ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-query-profiling.html
The following example demonstrates how to use Performance Schema statement events and stage events to retrieve data comparable to profiling information provided by SHOW PROFILES and SHOW PROFILE statements. The setup_actors table can be used to ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-setup-objects-table.html
Rows can be inserted into or deleted from setup_objects by users with the INSERT or DELETE privilege on the table. The setup_objects table controls whether the Performance Schema monitors particular objects. This table has a maximum size of 100 ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-handles-table.html
The value is one of READ, READ WITH SHARED LOCKS, READ HIGH PRIORITY, READ NO INSERT, WRITE ALLOW WRITE, WRITE CONCURRENT INSERT, WRITE LOW PRIORITY, or WRITE. The Performance Schema exposes table lock information through the table_handles table to ...
https://dev.mysql.com/doc/refman/8.4/en/problems-with-float.html
Suppose that you execute the following statements: CREATE TABLE t1(c1 FLOAT(53,0), c2 FLOAT(53,0)); INSERT INTO t1 VALUES('1e+52','-1e+52'); SELECT * FROM t1; On some platforms, the SELECT statement returns inf and -inf. Floating-point numbers ...