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https://dev.mysql.com/doc/refman/8.4/en/example-auto-increment.html
Note For a multiple-row insert, LAST_INSERT_ID() and mysql_insert_id() actually return the AUTO_INCREMENT key from the first of the inserted rows. For example, if the animals table contained indexes PRIMARY KEY (grp, id) and INDEX (id), MySQL would ...You can also explicitly assign 0 to the column to generate sequence numbers, unless the NO_AUTO_VALUE_ON_ZERO SQL mode is ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-columns-table.html
COLUMN_KEY Whether the column is indexed: If COLUMN_KEY is empty, the column either is not indexed or is indexed only as a secondary column in a multiple-column, nonunique index. If COLUMN_KEY is PRI, the column is a PRIMARY KEY or is one of the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning.html
Data Characteristics and Compression A key determinant of the efficiency of compression in reducing the size of data files is the nature of the data itself. It might be that the primary key (clustered) index, which contains the data for all columns ... Most often, the internal optimizations described in InnoDB Data Storage and Compression ensure that the system runs well with compressed ...
https://dev.mysql.com/doc/refman/8.4/en/insert-select.html
| TABLE table_name | VALUES row_constructor_list } [ON DUPLICATE KEY UPDATE assignment_list] value: {expr | DEFAULT} value_list: value [, value] ... TABLE as well: Specify IGNORE to ignore rows that would cause duplicate-key violations. ON DUPLICATE ... INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE] [INTO] tbl_name [PARTITION (partition_name [, partition_name] ...)] [(col_name [, col_name] ...)] { SELECT ...
https://dev.mysql.com/doc/refman/8.4/en/is-null-optimization.html
This optimization can handle one IS NULL for any key part. In the following query, MySQL uses key lookups only on the expression (t1.a=t2.a AND t2.a IS NULL) and is not able to use the key part on b: SELECT * FROM t1, t2 WHERE (t1.a=t2.a AND t2.a IS ... MySQL can perform the same optimization on col_name IS NULL that it can use for col_name = ...
https://dev.mysql.com/doc/refman/8.4/en/json-function-reference.html
Table 14.22 JSON Functions Name Description Deprecated -> Return value from JSON column after evaluating path; equivalent to JSON_EXTRACT(). ->> Return value from JSON column after evaluating path and unquoting the result; equivalent to ...
https://dev.mysql.com/doc/refman/8.4/en/kerberos-pluggable-authentication.html
Security: Kerberos uses tickets together with symmetric-key cryptography, enabling authentication without sending passwords over the network. KDC: The key distribution center, comprising the AS and TGS: AS: The authentication server; provides the ...
https://dev.mysql.com/doc/refman/8.4/en/keyring-plugin-installation.html
Keyring service consumers require that a keyring component or plugin be installed: To use a keyring plugin, begin with the instructions here. (Also, for general information about installing plugins, see Section 7.6.1, “Installing and Uninstalling ...To be usable by the server, the plugin library file must be located in the MySQL plugin directory (the directory named by the plugin_dir system ...
https://dev.mysql.com/doc/refman/8.4/en/linux-installation-yum-repo.html
Install the RPM you downloaded for your system, for example: $> sudo yum localinstall mysql84-community-release-{platform}-{version-number}.noarch.rpm The installation command adds the MySQL Yum repository to your system's repository list and ...
https://dev.mysql.com/doc/refman/8.4/en/load-xml.html
Suppose that we have a table named person, created as shown here: USE test; CREATE TABLE person ( person_id INT NOT NULL PRIMARY KEY, fname VARCHAR(40) NULL, lname VARCHAR(40) NULL, created TIMESTAMP ); Suppose further that this table is initially ...The tagname in the optional ROWS IDENTIFIED BY clause must also be given as a literal string, and must be surrounded by angle brackets (< and ...