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https://dev.mysql.com/doc/refman/8.4/en/invisible-columns.html
An invisible column is normally hidden to queries, but can be accessed if explicitly referenced. As an illustration of when invisible columns may be useful, suppose that an application uses SELECT * queries to access a table, and must continue to ...
https://dev.mysql.com/doc/refman/8.4/en/join.html
MySQL supports the following JOIN syntax for the table_references part of SELECT statements and multiple-table DELETE and UPDATE statements: table_references: escaped_table_reference [, escaped_table_reference] ... index_hint: { USE {INDEX|KEY} ...
https://dev.mysql.com/doc/refman/8.4/en/load-data-local-security.html
The LOAD DATA statement loads a data file into a table. The statement can load a file located on the server host, or, if the LOCAL keyword is specified, on the client host. In theory, a patched server could tell the client program to transfer a ...
https://dev.mysql.com/doc/refman/8.4/en/merge-table-problems.html
The following are known problems with MERGE tables: MERGE child tables are locked through the parent table. If the parent is a temporary table, it is not locked, and thus the child tables are also not locked; this means that parallel use of the ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-replication-schema.html
ndb_apply_status Table ndb_binlog_index Table ndb_replication Table Replication in NDB Cluster makes use of a number of dedicated tables in the mysql database on each MySQL Server instance acting as an SQL node in both the cluster being replicated ...
https://dev.mysql.com/doc/refman/8.4/en/problems-with-null.html
The concept of the NULL value is a common source of confusion for newcomers to SQL, who often think that NULL is the same thing as an empty string ''. For example, the following statements are completely different: mysql> INSERT INTO my_table ...
https://dev.mysql.com/doc/refman/8.4/en/source-configuration-options.html
The CMake program provides a great deal of control over how you configure a MySQL source distribution. Typically, you do this using options on the CMake command line. For information about options supported by CMake, run either of these commands in ...
https://dev.mysql.com/doc/refman/8.4/en/switchable-optimizations.html
Its value is a set of flags, each of which has a value of on or off to indicate whether the corresponding optimizer behavior is enabled or disabled. This variable has global and session values and can be changed at runtime. To see the current set of ...
https://dev.mysql.com/doc/refman/8.4/en/table.html
TABLE is a DML statement which returns rows and columns of the named table. Given the existence of a table named t, the following two statements produce identical output: TABLE t; SELECT * FROM t; You can order and limit the number of rows produced ...
https://dev.mysql.com/doc/extending-mysql/8.4/en/plugin-types.html
The plugin API enables creation of plugins that implement several capabilities: Loadable functions (UDFs) Storage engines Full-text parsers Daemons INFORMATION_SCHEMA tables Semisynchronous replication Auditing Authentication Password validation ...