The ndb_transid_mysql_connection_map table
provides a mapping between NDB transactions,
NDB transaction coordinators, and MySQL Servers
attached to a MySQL Cluster as API nodes. This information is used
when populating the
server_operations and
server_transactions tables of
the ndbinfo MySQL Cluster
information database.
INFORMATION_SCHEMA Name | SHOW Name | Remarks |
|---|---|---|
mysql_connection_id | MySQL Server connection ID | |
node_id | Transaction coordinator node ID | |
ndb_transid | NDB transaction ID |
The mysql_connection_id is the same as the
connection or session ID shown in the output of
SHOW PROCESSLIST.
There are no SHOW statements associated with
this table.
This is a nonstandard table, specific to MySQL Cluster. It is
implemented as an INFORMATION_SCHEMA plugin;
you can verify that it is supported by checking the output of
SHOW PLUGINS. If
ndb_transid_mysql_connection_map support is
enabled, the output from this statement includes a plugin having
this name, of type INFORMATION SCHEMA, and
having status ACTIVE, as shown here (using
emphasized text):
mysql> SHOW PLUGINS;
+----------------------------------+--------+--------------------+---------+---------+
| Name | Status | Type | Library | License |
+----------------------------------+--------+--------------------+---------+---------+
| binlog | ACTIVE | STORAGE ENGINE | NULL | GPL |
| mysql_native_password | ACTIVE | AUTHENTICATION | NULL | GPL |
| mysql_old_password | ACTIVE | AUTHENTICATION | NULL | GPL |
| CSV | ACTIVE | STORAGE ENGINE | NULL | GPL |
| MEMORY | ACTIVE | STORAGE ENGINE | NULL | GPL |
| MRG_MYISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |
| MyISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |
| PERFORMANCE_SCHEMA | ACTIVE | STORAGE ENGINE | NULL | GPL |
| BLACKHOLE | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ARCHIVE | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ndbcluster | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ndbinfo | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ndb_transid_mysql_connection_map | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| InnoDB | ACTIVE | STORAGE ENGINE | NULL | GPL |
| INNODB_TRX | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_LOCKS | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_LOCK_WAITS | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_CMP | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_CMP_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_CMPMEM | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| INNODB_CMPMEM_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL |
| partition | ACTIVE | STORAGE ENGINE | NULL | GPL |
+----------------------------------+--------+--------------------+---------+---------+
22 rows in set (0.00 sec)
The plugin is enabled by default. You can disable it (or force the
server not to run unless the plugin starts) by starting the server
with the
--ndb-transid-mysql-connection-map
option. If the plugin is disabled, the status is shown by
SHOW PLUGINS as
DISABLED. The plugin cannot be enabled or
disabled at runtime.
Although the names of this table and its columns are displayed using lowercase, you can use uppercase or lowercase when referring to them in SQL statements.
For this table to be created, the MySQL Server must be a binary
supplied with the MySQL Cluster distribution, or one built from
the MySQL Cluster sources with NDB
storage engine support enabled. It is not available in the
standard MySQL 5.6 Server.