This section provides detailed information about MySQL server
status variables that relate to MySQL Cluster and the
NDB storage engine. For status
variables not specific to MySQL Cluster, and for general
information on using status variables, see
Section 5.1.6, “Server Status Variables”.
The MySQL server can ask the
NDBCLUSTER storage engine if it
knows about a table with a given name. This is called
discovery.
Handler_discover indicates
the number of times that tables have been discovered using
this mechanism.
Ndb_api_wait_exec_complete_count_session
The number of times a thread has been blocked in this client
session while waiting for execution of an operation to
complete. This includes all
execute()
calls as well as implicit implicit executes for blob and
auto-increment operations not visible to clients.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_exec_complete_count_slave
The number of times a thread has been blocked by this slave
while waiting for execution of an operation to complete.
This includes all
execute()
calls as well as implicit implicit executes for blob and
auto-increment operations not visible to clients.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_exec_complete_count
The number of times a thread has been blocked by this MySQL
Server (SQL node) while waiting for execution of an
operation to complete. This includes all
execute()
calls as well as implicit implicit executes for blob and
auto-increment operations not visible to clients.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_scan_result_count_session
The number of times a thread has been blocked in this client session while waiting for a scan-based signal, such as when waiting for more results from a scan, or when waiting for a scan to close.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_scan_result_count_slave
The number of times a thread has been blocked by this slave while waiting for a scan-based signal, such as when waiting for more results from a scan, or when waiting for a scan to close.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_scan_result_count
The number of times a thread has been blocked by this MySQL Server (SQL node) while waiting for a scan-based signal, such as when waiting for more results from a scan, or when waiting for a scan to close.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_meta_request_count_session
The number of times a thread has been blocked in this client session waiting for a metadata-based signal, such as is expected for DDL requests, new epochs, and seizure of transaction records.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_meta_request_count_slave
The number of times a thread has been blocked by this slave waiting for a metadata-based signal, such as is expected for DDL requests, new epochs, and seizure of transaction records.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_meta_request_count
The number of times a thread has been blocked by this MySQL Server (SQL node) waiting for a metadata-based signal, such as is expected for DDL requests, new epochs, and seizure of transaction records.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_nanos_count_session
Total time (in nanoseconds) spent in this client session waiting for any type of signal from the data nodes.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_wait_nanos_count_slave
Total time (in nanoseconds) spent by this slave waiting for any type of signal from the data nodes.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Total time (in nanoseconds) spent by this MySQL Server (SQL node) waiting for any type of signal from the data nodes.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_bytes_sent_count_session
Amount of data (in bytes) sent to the data nodes in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_bytes_sent_count_slave
Amount of data (in bytes) sent to the data nodes by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Amount of data (in bytes) sent to the data nodes by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_bytes_received_count_session
Amount of data (in bytes) received from the data nodes in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_bytes_received_count_slave
Amount of data (in bytes) received from the data nodes by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Amount of data (in bytes) received from the data nodes by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_start_count_session
The number of transactions started in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_start_count_slave
The number of transactions started by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of transactions started by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_commit_count_session
The number of transactions committed in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_commit_count_slave
The number of transactions committed by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of transactions committed by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_abort_count_session
The number of transactions aborted in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_abort_count_slave
The number of transactions aborted by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of transactions aborted by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_close_count_session
The number of transactions closed in this client session.
This value may be greater than the sum of
Ndb_api_trans_commit_count_session
and
Ndb_api_trans_abort_count_session,
since some transactions may have been rolled back.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_close_count_slave
The number of transactions closed by this slave. This value
may be greater than the sum of
Ndb_api_trans_commit_count_slave
and
Ndb_api_trans_abort_count_slave,
since some transactions may have been rolled back.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of transactions closed by this MySQL Server (SQL
node). This value may be greater than the sum of
Ndb_api_trans_commit_count
and
Ndb_api_trans_abort_count,
since some transactions may have been rolled back.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations in this client session based on or using primary keys. This includes operations on blob tables, implicit unlock operations, and auto-increment operations, as well as user-visible primary key operations.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations by this slave based on or using primary keys. This includes operations on blob tables, implicit unlock operations, and auto-increment operations, as well as user-visible primary key operations.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations by this MySQL Server (SQL node) based on or using primary keys. This includes operations on blob tables, implicit unlock operations, and auto-increment operations, as well as user-visible primary key operations.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations in this client session based on or using unique keys.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations by this slave based on or using unique keys.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of operations by this MySQL Server (SQL node) based on or using unique keys.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_table_scan_count_session
The number of table scans that have been started in this client session, including scans of internal tables,.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_table_scan_count_slave
The number of table scans that have been started by this slave, including scans of internal tables,.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of table scans that have been started by this MySQL Server (SQL node), including scans of internal tables,.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_range_scan_count_session
The number of range scans that have been started in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_range_scan_count_slave
The number of range scans that have been started by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of range scans that have been started by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_pruned_scan_count_session
The number of scans in this client session that have been pruned to a single partition.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_pruned_scan_count_slave
The number of scans by this slave that have been pruned to a single partition.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of scans by this MySQL Server (SQL node) that have been pruned to a single partition.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_scan_batch_count_session
The number of batches of rows received in this client session. 1 batch is defined as 1 set of scan results from a single fragment.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_scan_batch_count_slave
The number of batches of rows received by this slave. 1 batch is defined as 1 set of scan results from a single fragment.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of batches of rows received by this MySQL Server (SQL node). 1 batch is defined as 1 set of scan results from a single fragment.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_read_row_count_session
The total number of rows that have been read in this client session. This includes all rows read by any primary key, unique key, or scan operation made in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The total number of rows that have been read by this slave. This includes all rows read by any primary key, unique key, or scan operation made by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The total number of rows that have been read by this MySQL Server (SQL node). This includes all rows read by any primary key, unique key, or scan operation made by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_local_read_row_count_session
The total number of rows that have been read in this client session. This includes all rows read by any primary key, unique key, or scan operation made in this client session.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it relates to the current session only,
and is not affected by any other clients of this
mysqld.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_local_read_row_count_slave
The total number of rows that have been read by this slave. This includes all rows read by any primary key, unique key, or scan operation made by this slave.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope. If this
MySQL server does not act as a replication slave, or does
not use NDB tables, this value is always 0.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_trans_local_read_row_count
The total number of rows that have been read by this MySQL Server (SQL node). This includes all rows read by any primary key, unique key, or scan operation made by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_event_data_count_injector
The number of row change events received by the NDB binlog injector thread.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of row change events received by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_event_nondata_count_injector
The number of events received, other than row change events, by the NDB binlog injector thread.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of events received, other than row change events, by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
Ndb_api_event_bytes_count_injector
The number of bytes of events received by the NDB binlog injector thread.
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
The number of bytes of events received by this MySQL Server (SQL node).
Although this variable can be read using either
SHOW GLOBAL
STATUS or
SHOW SESSION
STATUS, it is effectively global in scope.
For more information, see Section 17.5.15, “NDB API Statistics Counters and Variables”.
If the server is acting as a MySQL Cluster node, then the value of this variable its node ID in the cluster.
If the server is not part of a MySQL Cluster, then the value of this variable is 0.
If the server is part of a MySQL Cluster, the value of this variable is the host name or IP address of the Cluster management server from which it gets its configuration data.
If the server is not part of a MySQL Cluster, then the value of this variable is an empty string.
If the server is part of a MySQL Cluster, the value of this variable is the number of the port through which it is connected to the Cluster management server from which it gets its configuration data.
If the server is not part of a MySQL Cluster, then the value of this variable is 0.
Used in MySQL Cluster Replication conflict resolution, this variable shows the number of times that a row was not applied on the current SQL node due to “greatest timestamp wins” conflict resolution since the last time that this mysqld was started.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Used in MySQL Cluster Replication conflict resolution, this variable shows the number of times that a row was not applied as the result of “same timestamp wins” conflict resolution on a given mysqld since the last time it was restarted.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Used in MySQL Cluster Replication conflict resolution, this
variable shows the number of rows found to be in conflict
using NDB$EPOCH() conflict resolution on
a given mysqld since the last time it was
restarted.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Used in MySQL Cluster Replication conflict resolution, this
variable shows the number of rows found to be in conflict
using NDB$EPOCH_TRANS() conflict
resolution on a given mysqld since the
last time it was restarted.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Ndb_conflict_trans_row_conflict_count
Used in MySQL Cluster Replication conflict resolution, this status variable shows the number of rows found to be directly in-conflict by a transactional conflict function on a given mysqld since the last time it was restarted.
Currently, the only transactional conflict detection
function supported by MySQL Cluster is NDB$EPOCH_TRANS(), so
this status variable is effectively the same as
Ndb_conflict_fn_epoch_trans.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Ndb_conflict_trans_row_reject_count
Used in MySQL Cluster Replication conflict resolution, this
status variable shows the total number of rows realigned due
to being determined as conflicting by a transactional
conflict detection function. This includes not only
Ndb_conflict_trans_row_conflict_count,
but any rows in or dependent on conflicting transactions.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Ndb_conflict_trans_reject_count
Used in MySQL Cluster Replication conflict resolution, this status variable shows the number of transactions found to be in conflict by a transactional conflict detection function.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Ndb_conflict_trans_detect_iter_count
Used in MySQL Cluster Replication conflict resolution, this
shows the number of internal iterations required to commit
an epoch transaction. Should be (slightly) greater than or
equal to
Ndb_conflict_trans_conflict_commit_count.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Ndb_conflict_trans_conflict_commit_count
Used in MySQL Cluster Replication conflict resolution, this shows the number of epoch transactions committed after they required transactional conflict handling.
For more information, see Section 17.6.11, “MySQL Cluster Replication Conflict Resolution”.
Provides the number of round trips to the
NDB kernel made by operations.
If the server is part of a MySQL Cluster, the value of this variable is the number of data nodes in the cluster.
If the server is not part of a MySQL Cluster, then the value of this variable is 0.
The total number of joins pushed down to the NDB kernel for
distributed handling on the data nodes. Note that joins
tested using EXPLAIN that can
be pushed down contribute to this number. Added in MySQL
Cluster NDB 7.2.0.
The number of joins that were pushed down to the NDB kernel but that could not be handled there. Added in MySQL Cluster NDB 7.2.0.
The number of joins successfully pushed down to
NDB and executed there. Added
in MySQL Cluster NDB 7.2.0.
The number of rows returned to mysqld
from the NDB kernel by joins that were pushed down. Note
that executing EXPLAIN on
joins that can be pushed down to
NDB does not add to this
number. Added in MySQL Cluster NDB 7.2.0.
This variable holds a count of the number of scans executed
by NDBCLUSTER since the MySQL
Cluster was last started where
NDBCLUSTER was able to use
partition pruning.
Using this variable together with
Ndb_scan_count can be
helpful in schema design to maximize the ability of the
server to prune scans to a single table partition, thereby
involving only a single data node.
This variable holds a count of the total number of scans
executed by NDBCLUSTER since
the MySQL Cluster was last started.

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