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https://dev.mysql.com/doc/refman/8.0/en/replication-features-auto-increment.html
(Bug #45677) An INSERT into a table that has a composite primary key that includes an AUTO_INCREMENT column that is not the first column of this composite key is not safe for statement-based logging or replication. (Bug #11754117, Bug #45670) This ... Statement-based replication of AUTO_INCREMENT, LAST_INSERT_ID(), and TIMESTAMP values is carried out subject to the following exceptions: A statement invoking a trigger or function that causes an update to an AUTO_INCREMENT column is not replicated correctly using statement-based ...
https://dev.mysql.com/doc/refman/8.0/en/cost-model.html
The primary key for the server_cost table is the cost_name column, so it is not possible to create multiple entries for any cost estimate. Increasing this value causes a query plan that compares many keys to become more expensive. The primary key ...
https://dev.mysql.com/doc/refman/8.0/en/derived-condition-pushdown-optimization.html
MySQL 8.0.22 and later supports derived condition pushdown for eligible subqueries. When a derived table cannot be merged into the outer query (for example, if the derived table uses aggregation), pushing the outer WHERE condition down to the ...
https://dev.mysql.com/doc/refman/8.0/en/index-hints.html
index_hint: USE {INDEX|KEY} [FOR {JOIN|ORDER BY|GROUP BY}] ([index_list]) | {IGNORE|FORCE} {INDEX|KEY} [FOR {JOIN|ORDER BY|GROUP BY}] (index_list) index_list: index_name [, index_name] ... row *************************** id: 1 select_type: DELETE ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-benefits.html
If you split up related data into different tables, you can set up foreign keys that enforce referential integrity. When you design a database with appropriate primary key columns for each table, operations involving those columns are automatically ... InnoDB tables have the following benefits: If the server unexpectedly exits because of a hardware or software issue, regardless of what was happening in the database at the time, you don't need to do anything special after restarting the ...
https://dev.mysql.com/doc/refman/8.0/en/subquery-optimization-with-exists.html
WHERE subquery_where AND (outer_expr=inner_expr OR inner_expr IS NULL)) The need to evaluate the extra IS NULL condition is why MySQL has the ref_or_null access method: mysql> EXPLAIN SELECT outer_expr IN (SELECT t2.maybe_null_key FROM t2, t3 WHERE ... Certain optimizations are applicable to comparisons that use the IN (or =ANY) operator to test subquery ...
https://dev.mysql.com/doc/refman/8.0/en/declare-handler.html
HANDLER statement had not been present, MySQL would have taken the default action (EXIT) after the second INSERT failed due to the PRIMARY KEY constraint, and SELECT @x would have returned 2. statement handler_action: { CONTINUE | EXIT | UNDO } ...
https://dev.mysql.com/doc/refman/8.0/en/information-schema-introduction.html
Beginning with MySQL 8.0.30, information about generated invisible primary keys is visible by default in all INFORMATION_SCHEMA tables describing table columns, keys, or both, such as the COLUMNS and STATISTICS tables. INFORMATION_SCHEMA provides ...
https://dev.mysql.com/doc/refman/8.0/en/information-schema-table-constraints-table.html
The value can be UNIQUE, PRIMARY KEY, FOREIGN KEY, or (as of MySQL 8.0.16) CHECK. The UNIQUE and PRIMARY KEY information is about the same as what you get from the Key_name column in the output from SHOW INDEX when the Non_unique column is 0. The ...
https://dev.mysql.com/doc/refman/8.0/en/replication-features-row-searches.html
If there are suitable indexes, one index is selected from the candidates, in the following priority order: A primary key. If the algorithm is able to select a primary key or a unique index where every column in the index has a NOT NULL attribute, it ... When a replica using row-based replication format applies an UPDATE or DELETE operation, it must search the relevant table for the matching ...