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https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam-bulk-data-loading.html
These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT Statements”. LOAD DATA performs the preceding optimization automatically if the MyISAM table into which you insert data is empty.
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/backup-performance.html
When optimizing and tuning the backup procedure, measure both the raw performance (how long it takes the backup to complete) and the amount of overhead on the database server. See Section 13.2, “Optimizing Restore Performance” for performance ...
https://dev.mysql.com/doc/internals/en/optimizer-constants-constant-tables.html
The optimizer does some of the transformation because of constant propagation, which we described earlier. A MySQL constant is something more than a mere literal in the query. unique_not_null_column INT NOT NULL UNIQUE then this expression FROM ...
https://dev.mysql.com/doc/internals/en/optimizer-index-join-type.html
Consider this query: SELECT column1 FROM Table1; If column1 is indexed, then the optimizer may choose to retrieve the values from the index rather than from the table. For this query: SELECT column1, column2 FROM Table1; the optimizer will use join ...An index which is used this way is called a covering index in most ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-bulk-data-loading.html
These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT Statements”. For optimal performance when loading data into an InnoDB FULLTEXT index, follow this set of steps: Define a column ...
https://dev.mysql.com/doc/internals/en/optimizer-code-concepts.html
This section discusses key optimizer concepts, terminology, and how these are reflected in the MySQL server source code.
https://dev.mysql.com/doc/internals/en/optimizer-definitions.html
This description uses a narrow definition: The optimizer is the set of routines which decide what execution path the DBMS should take for queries. To make that easy, this description includes notes referring to the relevant file and routine, such ...MySQL changes these routines frequently, so you should compare what is said here with what's in the current source ...
https://dev.mysql.com/doc/internals/en/optimizer-determining-join-type.html
The optimizer can use the join type to pick a driver expression. When evaluating a conditional expression, MySQL decides what join type the expression has. (Again: despite the word “join”, this applies for all conditional expressions, not just ...
https://dev.mysql.com/doc/internals/en/optimizer-folding-constants.html
It is quite easy for the optimizer to put such expressions together. A transformation takes place for this expression: WHERE column1 = 1 + 2 which becomes: WHERE column1 = 3 Before you say, “but I never would write 1 + 2 in the first place”, ...
https://dev.mysql.com/doc/internals/en/optimizer-late-nulls-filtering.html
This optimization reuses the null_rejecting attribute produced by the early NULLs filtering code (see Section 7.3.1.1, “Early NULLs Filtering”). Suppose we have a query plan with table tblX being accessed via the ref access method: ...