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https://dev.mysql.com/mysql-cluster-online-add-node-example.html
In this section we provide a detailed example illustrating how to add new NDB Cluster data nodes online, starting with an NDB Cluster having 2 data nodes in a single node group and concluding with a cluster having 4 data nodes in 2 node groups.
https://dev.mysql.com/alter-table.html
Running ALTER TABLE tbl_name ENGINE=INNODB on an existing InnoDB table performs a “null” ALTER TABLE operation, which can be used to defragment an InnoDB table, as described in Section 15.11.4, “Defragmenting a Table”. As of MySQL 8.0.14, ...
https://dev.mysql.com/date-and-time-functions.html
For example: mysql> SELECT DAYOFMONTH('2001-11-00'), MONTH('2005-00-00'); -> 0, 0 Other functions expect complete dates and return NULL for incomplete dates. For example: mysql> SELECT DATE_ADD('2006-05-00',INTERVAL 1 DAY); -> NULL mysql> SELECT ...
https://dev.mysql.com/data-masking-reference.html
Return value: The masked string, or NULL if either margin is negative. Return value: The masked string, or NULL if either margin is negative. Return value: The masked Social Security number as a string, or NULL if the argument is not the correct ...
https://dev.mysql.com/innodb-parameters.html
daemon_memcached_engine_lib_path Property Value Command-Line Format --daemon-memcached-engine-lib-path=dir_name System Variable daemon_memcached_engine_lib_path Scope Global Dynamic No SET_VAR Hint Applies No Type Directory name Default Value NULL ... System variables that are true or false can be enabled at server startup by naming them, or disabled by using a --skip- ...
https://dev.mysql.com/innodb-row-format.html
An SQL NULL value reserves one or two bytes in the record directory. An SQL NULL value reserves zero bytes in the data part of the record if stored in a variable-length column. Reserving fixed space for NULL values permits columns to be updated in ... The row format of a table determines how its rows are physically stored, which in turn can affect the performance of queries and DML ...
https://dev.mysql.com/partitioning-management-range-list.html
Adding and dropping of range and list partitions are handled in a similar fashion, so we discuss the management of both sorts of partitioning in this section. For information about working with tables that are partitioned by hash or key, see ...
https://dev.mysql.com/control-flow-functions.html
If no comparison or condition is true, the result after ELSE is returned, or NULL if there is no ELSE part. The CASE statement cannot have an ELSE NULL clause, and it is terminated with END CASE instead of END. If only one of expr2 or expr3 is ...
https://dev.mysql.com/mysql-cluster-online-operations.html
This does not perform any defragmentation, which requires an OPTIMIZE TABLE or null ALTER TABLE statement. The columns must permit NULL values and not have any explicit default value other than NULL. row *************************** Table: t1 Create ... MySQL NDB Cluster 8.0 supports online table schema changes using the standard ALTER TABLE syntax employed by the MySQL Server (ALGORITHM=DEFAULT|INPLACE|COPY), and described ...
https://dev.mysql.com/show-index.html
row *************************** Table: city Non_unique: 0 Key_name: PRIMARY Seq_in_index: 1 Column_name: ID Collation: A Cardinality: 4188 Sub_part: NULL Packed: NULL Null: Index_type: BTREE Comment: Index_comment: Visible: YES Expression: NULL ...
Document created the 26/06/2006, last modified the 26/10/2018
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