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https://dev.mysql.com/doc/refman/8.4/en/table-locking.html
InnoDB tables use row-level locking so that multiple sessions and applications can read from and write to the same table simultaneously, without making each other wait or producing inconsistent results. For this storage engine, avoid using the LOCK ...See Chapter 17, The InnoDB Storage Engine for more details about this storage ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-dictionary-tables.html
dictionary_tables contains the columns listed here: table_id The table' unique ID database_name Name of the database containing the table table_name Name of the table status The table status; one of New, Changed, Retrieved, Invalid, or Altered.
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 ...See Section 15.2.18, “UNION Clause”, Section 15.2.4, “EXCEPT Clause”, and Section 15.2.8, “INTERSECT Clause”, for more information and ...
https://dev.mysql.com/doc/refman/8.4/en/alter-table-generated-columns.html
ALTER TABLE operations permitted for generated columns are ADD, MODIFY, and CHANGE. CREATE TABLE t1 (c1 INT); ALTER TABLE t1 ADD COLUMN c2 INT GENERATED ALWAYS AS (c1 + 1) STORED; The data type and expression of generated columns can be modified.
https://dev.mysql.com/doc/x-devapi-userguide/en/devapi-users-working-with-relational-tables.html
The X DevAPI SQL CRUD functions allow you to work with relational tables in manners similar to using traditional SQL statements. The following code sample shows how to use the add() and select() methods of the X DevAPI SQL CRUD functions, which are ...
https://dev.mysql.com/doc/refman/8.4/en/replication-rules-table-options.html
The replica checks for and evaluates table options only if either of the following two conditions is true: No matching database options were found. When viewed in terms of events, the process of checking table options is the same for both row-based ...One or more database options were found, and were evaluated to arrive at an “execute” condition according to the rules described in the previous section (see Section 19.2.5.1, “Evaluation of Database-Level Replication and Binary Logging ...
https://dev.mysql.com/doc/refman/8.4/en/temporary-table-problems.html
Temporary tables created with CREATE TEMPORARY TABLE have the following limitations: TEMPORARY tables are supported only by the InnoDB, MEMORY, MyISAM, and MERGE storage engines. Use ALTER TABLE instead: ALTER TABLE old_name RENAME new_name; You ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-generated-columns.html
It is permitted to mix VIRTUAL and STORED columns within a table. A function is deterministic if, given the same data in tables, multiple invocations produce the same result, independently of the connected user. A generated column definition can ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-files-table.html
The FILES table provides information about the files in which MySQL tablespace data is stored. In NDB Cluster, this table also provides information about the files in which NDB Cluster Disk Data tables are stored. The FILES table has these columns: ...For additional information specific to InnoDB, see InnoDB Notes, later in this section; for additional information specific to NDB Cluster, see NDB ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-threads-table.html
The threads table contains a row for each server thread. When the Performance Schema initializes, it populates the threads table based on the threads in existence then. The INSTRUMENTED and HISTORY column values for new threads are determined by ...