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https://dev.mysql.com/doc/refman/8.4/en/server-system-variables.html
The following table shows some possible values for authentication_policy and the policy that each establishes for creating or altering accounts. CREATE TABLE and ALTER TABLE having a CHARACTER SET utf8mb4 clause without a COLLATION clause, either ...
https://dev.mysql.com/doc/refman/8.4/en/create-table.html
However, prefix lengths for index specifications in CREATE TABLE, ALTER TABLE, and CREATE INDEX statements are interpreted as number of characters for nonbinary string types (CHAR, VARCHAR, TEXT) and number of bytes for binary string types (BINARY, ...(Some valid select or union statement) CREATE TABLE creates a table with the given ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
A newly created secondary index contains only the committed data in the table at the time the CREATE INDEX or ALTER TABLE statement finishes executing. Dropping an index DROP INDEX name ON table; ALTER TABLE tbl_name DROP INDEX name; The table ...
https://dev.mysql.com/doc/refman/8.4/en/lock-tables.html
Note If you use ALTER TABLE on a locked table, it may become unlocked. For example, if you attempt a second ALTER TABLE operation, the result may be an error Table 'tbl_name' was not locked with LOCK TABLES. To handle this, lock the table again ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-parameters.html
innodb_online_alter_log_max_size Command-Line Format --innodb-online-alter-log-max-size=# System Variable innodb_online_alter_log_max_size Scope Global Dynamic Yes SET_VAR Hint Applies No Type Integer Default Value 134217728 Minimum Value 65536 ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-table-import.html
Also, you should export all foreign key related tables at the same logical point in time, as ALTER TABLE ... (Before importing, you must discard the tablespace of the receiving table.) mysql> ALTER TABLE t1 DISCARD TABLESPACE; On the source ... This ...As a faster way of moving data than importing a dump file, which requires reinserting data and rebuilding ...
https://dev.mysql.com/doc/refman/8.4/en/mysqldump.html
Alternatively, you can enable the show_create_table_skip_secondary_engine system variable prior to using mysqldump. --disable-keys, -K Command-Line Format --disable-keys For each table, surround the INSERT statements with /*!40000 ALTER TABLE ...It ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-restore.html
This may be desirable when backing up and restoring between different schema versions with primary key changes on one or more tables, and it appears that performing the restore operation using ndb_restore is simpler or more efficient than issuing ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management-exchange.html
In addition to the ALTER, INSERT, and CREATE privileges usually required for ALTER TABLE statements, you must have the DROP privilege to perform ALTER TABLE ... You should also be aware of the following effects of ALTER TABLE ... The IGNORE keyword ...Table nt contains no foreign key references, and no other table has any foreign keys that refer to ...
https://dev.mysql.com/doc/refman/8.4/en/explain-output.html
To fix this disparity between column lengths, use ALTER TABLE to lengthen ActualPC from 10 characters to 15 characters: mysql> ALTER TABLE tt MODIFY ActualPC VARCHAR(15); Now tt.ActualPC and et.EMPLOYID are both VARCHAR(15). EXPLAIN returns a row of ... The EXPLAIN statement provides information about how MySQL executes ...