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https://dev.mysql.com/doc/refman/8.4/en/data-type-defaults.html
Data type specifications can have explicit or implicit default values. A DEFAULT value clause in a data type specification explicitly indicates a default value for a column. Examples: CREATE TABLE t1 ( i INT DEFAULT -1, c VARCHAR(10) DEFAULT '', ...
https://dev.mysql.com/doc/refman/8.4/en/ddl-rewriter.html
MySQL 8.4 includes a ddl_rewriter plugin that modifies CREATE TABLE statements received by the server before it parses and executes them. The plugin removes ENCRYPTION, DATA DIRECTORY, and INDEX DIRECTORY clauses, which may be helpful when ...
https://dev.mysql.com/doc/refman/8.4/en/general-tablespaces.html
A general tablespace is a shared InnoDB tablespace that is created using CREATE TABLESPACE syntax. The server keeps tablespace metadata in memory for the lifetime of a tablespace. Multiple tables in fewer general tablespaces consume less memory for ...
https://dev.mysql.com/doc/refman/8.4/en/generated-column-index-optimizations.html
For example: CREATE TABLE t1 (f1 INT, gc INT AS (f1 + 1) STORED, INDEX (gc)); The generated column, gc, is defined as the expression f1 + 1. The column is also indexed and the optimizer can take that index into account during execution plan ...
https://dev.mysql.com/doc/refman/8.4/en/identifiers.html
Certain objects within MySQL, including database, table, index, column, alias, view, stored procedure, partition, tablespace, resource group and other object names are known as identifiers. Section 11.2.1, “Identifier Length Limits”, indicates ...
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 ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-create-table-external.html
There are different reasons for creating InnoDB tables externally; that is, creating tables outside of the data directory. Those reasons might include space management, I/O optimization, or placing tables on a storage device with particular ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-fulltext-index.html
Full-text indexes are created on text-based columns (CHAR, VARCHAR, or TEXT columns) to speed up queries and DML operations on data contained within those columns. A full-text index is defined as part of a CREATE TABLE statement or added to an ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-performance.html
Online DDL improves several aspects of MySQL operation: Applications that access the table are more responsive because queries and DML operations on the table can proceed while the DDL operation is in progress. Reduced locking and waiting for MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/merge-storage-engine.html
The MERGE storage engine, also known as the MRG_MyISAM engine, is a collection of identical MyISAM tables that can be used as one. “Identical” means that all tables have identical column data types and index information. You cannot merge MyISAM ...