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https://dev.mysql.com/doc/refman/8.4/en/optimizer-features-to-trace.html
Some features in the optimizer can be invoked many times during statement optimization and execution, and thus can make the trace grow beyond reason. They are: Greedy search: With an N-table join, this could explore factorial(N) plans. Range ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-server.html
This section discusses optimization techniques for the database server, primarily dealing with system configuration rather than tuning SQL statements. The information in this section is appropriate for DBAs who want to ensure performance and ...
https://dev.mysql.com/doc/refman/8.4/en/other-vendor-data-types.html
If you create a table with types used by other vendors and then issue a DESCRIBE tbl_name statement, MySQL reports the table structure using the equivalent MySQL types. To facilitate the use of code written for SQL implementations from other ...
https://dev.mysql.com/doc/refman/8.4/en/packet-too-large.html
A communication packet is a single SQL statement sent to the MySQL server, a single row that is sent to the client, or a binary log event sent from a replication source server to a replica. The largest possible packet that can be transmitted to or ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-columns-list.html
See Section 15.1.20, “CREATE TABLE Statement”, for additional information about PARTITION BY LIST COLUMNS() syntax. This is a variant of LIST partitioning that enables the use of multiple columns as partition keys, and for columns of data types ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations-functions.html
This section discusses limitations in MySQL Partitioning relating specifically to functions used in partitioning expressions. Each of these functions returns an integer only if it is passed an argument of an exact numeric type, such as one of the ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations-storage-engines.html
CREATE TABLE and ALTER TABLE statements that would cause a user-partitioned NDB table not to meet either or both of the following two requirements are not permitted, and fail with an error: The table must have an explicit primary key. In MySQL 8.4, ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-linear-hash.html
MySQL also supports linear hashing, which differs from regular hashing in that linear hashing utilizes a linear powers-of-two algorithm whereas regular hashing employs the modulus of the hashing function's value. We call this value V; it can be ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management-hash-key.html
Tables which are partitioned by hash or by key are very similar to one another with regard to making changes in a partitioning setup, and both differ in a number of ways from tables which have been partitioned by range or list. For that reason, ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-build-configuration.html
For example, to exclude stage and statement instrumentation, do this: $> cmake . \ -DDISABLE_PSI_STAGE=1 \ -DDISABLE_PSI_STATEMENT=1 For more information, see the descriptions of the DISABLE_PSI_XXX CMake options in Section 2.8.7, “MySQL ...It is ...