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https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
The CREATE INDEX statement only finishes after all transactions that are accessing the table are completed, so that the initial state of the index reflects the most recent contents of the table. A newly created secondary index contains only the ...
https://dev.mysql.com/doc/refman/8.4/en/ansi-diff-foreign-keys.html
In an SQL statement that inserts, deletes, or updates many rows, foreign key constraints (like unique constraints) are checked row-by-row. That is, constraints are only checked after the entire SQL statement has been processed. The MATCH clause in ...For example, if you define a RESTRICT type constraint, and there is a child row with several parent rows, InnoDB does not permit the deletion of any of the parent ...
https://dev.mysql.com/doc/refman/8.4/en/range-optimization.html
The range access method uses a single index to retrieve a subset of table rows that are contained within one or several index value intervals. Additionally, for BTREE indexes, comparison of a key part with a constant value is a range condition when ...The following sections describe conditions under which the optimizer uses range ...
https://dev.mysql.com/doc/relnotes/heatwave/en/news-9-2-0.html
This feature allows for the creation of secondary indexes during the bulk load process, reducing the need for additional ALTER TABLE statements. This feature automates the detection of record delimiters, field delimiters, and composite record ...
https://dev.mysql.com/doc/workbench/en/wb-table-editor-columns-tab.html
PK: PRIMARY KEY NN: NOT NULL UQ: UNIQUE INDEX BIN: BINARY UN: UNSIGNED ZF: ZEROFILL AI: AUTO_INCREMENT G: Generated Column This option is available as of MySQL Server 5.7. If you wish to create a composite primary key you can select multiple columns ... Use the Columns subtab to display and edit all the column information for a ...
https://dev.mysql.com/doc/refman/8.4/en/group-by-functional-dependence.html
The examples use the world database, which can be downloaded from https://dev.mysql.com/doc/index-other.html. A UNIQUE index over a NOT NULL column could be used instead of a primary key and the same functional dependence would apply. The following ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/backup-progress-table-update.html
Rename the original mysql.backup_progress table to mysql.backup_progress_old, and the mysql.backup_progress_new table to mysql.backup_progress. Note If you are working with a multiprimary Group Replication setting, make sure these privileges are ...
https://dev.mysql.com/doc/workbench/en/wb-relationship-tools.html
In such cases, the primary key is usually a composite key made up of the primary keys from the two original tables. Typically this occurs where an intermediary table is created to resolve a many-to-many relationship. A non-identifying relationship: ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-arbitrator-validity-summary.html
The arbitrator_validity_summary table provides a composite view of the arbitrator with regard to the cluster's data nodes. If it has more than 1 row for longer than a few moments, then either not all nodes are connected to the arbitrator, or all ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-auto-increment-handling.html
InnoDB provides a configurable locking mechanism that can significantly improve scalability and performance of SQL statements that add rows to tables with AUTO_INCREMENT columns. To use the AUTO_INCREMENT mechanism with an InnoDB table, an ...This ...