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MySQL NDB Cluster 7.5  /  Management of NDB Cluster  /  Quick Reference: NDB Cluster SQL Statements

7.9 Quick Reference: NDB Cluster SQL Statements

This section discusses several SQL statements that can prove useful in managing and monitoring a MySQL server that is connected to an NDB Cluster, and in some cases provide information about the cluster itself.

  • SHOW ENGINE NDB STATUS, SHOW ENGINE NDBCLUSTER STATUS

    The output of this statement contains information about the server's connection to the cluster, creation and usage of NDB Cluster objects, and binary logging for NDB Cluster replication.

    See SHOW ENGINE Statement, for a usage example and more detailed information.

  • SHOW ENGINES

    This statement can be used to determine whether or not clustering support is enabled in the MySQL server, and if so, whether it is active.

    See SHOW ENGINES Statement, for more detailed information.

    Note

    This statement does not support a LIKE clause. However, you can use LIKE to filter queries against the INFORMATION_SCHEMA.ENGINES table, as discussed in the next item.

  • SELECT * FROM INFORMATION_SCHEMA.ENGINES [WHERE ENGINE LIKE 'NDB%']

    This is the equivalent of SHOW ENGINES, but uses the ENGINES table of the INFORMATION_SCHEMA database. Unlike the case with the SHOW ENGINES statement, it is possible to filter the results using a LIKE clause, and to select specific columns to obtain information that may be of use in scripts. For example, the following query shows whether the server was built with NDB support and, if so, whether it is enabled:

    mysql> SELECT SUPPORT FROM INFORMATION_SCHEMA.ENGINES
        ->   WHERE ENGINE LIKE 'NDB%';
    +---------+
    | support |
    +---------+
    | ENABLED |
    +---------+

    See The INFORMATION_SCHEMA ENGINES Table, for more information.

  • SHOW VARIABLES LIKE 'NDB%'

    This statement provides a list of most server system variables relating to the NDB storage engine, and their values, as shown here, using NDB 7.6:

    mysql> SHOW VARIABLES LIKE 'NDB%';
    +--------------------------------------+---------------------------------------+
    | Variable_name                        | Value                                 |
    +--------------------------------------+---------------------------------------+
    | ndb_allow_copying_alter_table        | ON                                    |
    | ndb_autoincrement_prefetch_sz        | 1                                     |
    | ndb_batch_size                       | 32768                                 |
    | ndb_blob_read_batch_bytes            | 65536                                 |
    | ndb_blob_write_batch_bytes           | 65536                                 |
    | ndb_cache_check_time                 | 0                                     |
    | ndb_clear_apply_status               | ON                                    |
    | ndb_cluster_connection_pool          | 1                                     |
    | ndb_cluster_connection_pool_nodeids  |                                       |
    | ndb_connectstring                    | 127.0.0.1                             |
    | ndb_data_node_neighbour              | 0                                     |
    | ndb_default_column_format            | FIXED                                 |
    | ndb_deferred_constraints             | 0                                     |
    | ndb_distribution                     | KEYHASH                               |
    | ndb_eventbuffer_free_percent         | 20                                    |
    | ndb_eventbuffer_max_alloc            | 0                                     |
    | ndb_extra_logging                    | 1                                     |
    | ndb_force_send                       | ON                                    |
    | ndb_fully_replicated                 | OFF                                   |
    | ndb_index_stat_enable                | ON                                    |
    | ndb_index_stat_option                | loop_enable=1000ms,loop_idle=1000ms,
    loop_busy=100ms,update_batch=1,read_batch=4,idle_batch=32,check_batch=8,
    check_delay=10m,delete_batch=8,clean_delay=1m,error_batch=4,error_delay=1m,
    evict_batch=8,evict_delay=1m,cache_limit=32M,cache_lowpct=90,zero_total=0      |
    | ndb_join_pushdown                    | ON                                    |
    | ndb_log_apply_status                 | OFF                                   |
    | ndb_log_bin                          | ON                                    |
    | ndb_log_binlog_index                 | ON                                    |
    | ndb_log_empty_epochs                 | OFF                                   |
    | ndb_log_empty_update                 | OFF                                   |
    | ndb_log_exclusive_reads              | OFF                                   |
    | ndb_log_orig                         | OFF                                   |
    | ndb_log_transaction_id               | OFF                                   |
    | ndb_log_update_as_write              | ON                                    |
    | ndb_log_update_minimal               | OFF                                   |
    | ndb_log_updated_only                 | ON                                    |
    | ndb_mgmd_host                        | 127.0.0.1                             |
    | ndb_nodeid                           | 0                                     |
    | ndb_optimization_delay               | 10                                    |
    | ndb_optimized_node_selection         | 3                                     |
    | ndb_read_backup                      | OFF                                   |
    | ndb_recv_thread_activation_threshold | 8                                     |
    | ndb_recv_thread_cpu_mask             |                                       |
    | ndb_report_thresh_binlog_epoch_slip  | 10                                    |
    | ndb_report_thresh_binlog_mem_usage   | 10                                    |
    | ndb_row_checksum                     | 1                                     |
    | ndb_show_foreign_key_mock_tables     | OFF                                   |
    | ndb_slave_conflict_role              | NONE                                  |
    | ndb_table_no_logging                 | OFF                                   |
    | ndb_table_temporary                  | OFF                                   |
    | ndb_use_copying_alter_table          | OFF                                   |
    | ndb_use_exact_count                  | OFF                                   |
    | ndb_use_transactions                 | ON                                    |
    | ndb_version                          | 460301                                |
    | ndb_version_string                   | ndb-7.6.13                            |
    | ndb_wait_connected                   | 30                                    |
    | ndb_wait_setup                       | 30                                    |
    | ndbinfo_database                     | ndbinfo                               |
    | ndbinfo_max_bytes                    | 0                                     |
    | ndbinfo_max_rows                     | 10                                    |
    | ndbinfo_offline                      | OFF                                   |
    | ndbinfo_show_hidden                  | OFF                                   |
    | ndbinfo_table_prefix                 | ndb$                                  |
    | ndbinfo_version                      | 460301                                |
    +--------------------------------------+---------------------------------------+
    61 rows in set (0.02 sec)

    See Server System Variables, for more information.

  • SELECT * FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME LIKE 'NDB%';

    Although it is deprecated in NDB 7.5 and NDB 7.6, you can use this statement (and others accessing the INFORMATION_SCHEMA.GLOBAL_VARIABLES table) if show_compatibility_56 is enabled. (Querying the performance_schema.global_variables table is preferred; see next item.) It is equivalent to the SHOW VARIABLES statement described in the previous item, and provides almost identical output, as shown here:

    mysql> SET @@global.show_compatibility_56=ON;
    Query OK, 0 rows affected (0.00 sec)
    mysql> SELECT * FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES
        ->   WHERE VARIABLE_NAME LIKE 'NDB%';
    mysql> SELECT * FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME LIKE 'NDB%';
    +--------------------------------------+---------------------------------------+
    | VARIABLE_NAME                        | VARIABLE_VALUE                        |
    +--------------------------------------+---------------------------------------+
    | NDB_CLUSTER_CONNECTION_POOL_NODEIDS  |                                       |
    | NDB_LOG_BINLOG_INDEX                 | ON                                    |
    | NDB_WAIT_SETUP                       | 30                                    |
    | NDB_ROW_CHECKSUM                     | 1                                     |
    | NDB_WAIT_CONNECTED                   | 30                                    |
    | NDB_USE_EXACT_COUNT                  | OFF                                   |
    | NDB_RECV_THREAD_ACTIVATION_THRESHOLD | 8                                     |
    | NDB_READ_BACKUP                      | OFF                                   |
    | NDB_EVENTBUFFER_MAX_ALLOC            | 0                                     |
    | NDBINFO_DATABASE                     | ndbinfo                               |
    | NDB_LOG_APPLY_STATUS                 | OFF                                   |
    | NDB_JOIN_PUSHDOWN                    | ON                                    |
    | NDB_RECV_THREAD_CPU_MASK             |                                       |
    | NDBINFO_VERSION                      | 460301                                |
    | NDB_CONNECTSTRING                    | 127.0.0.1                             |
    | NDB_TABLE_NO_LOGGING                 | OFF                                   |
    | NDB_LOG_UPDATED_ONLY                 | ON                                    |
    | NDB_VERSION                          | 460301                                |
    | NDB_LOG_UPDATE_MINIMAL               | OFF                                   |
    | NDB_OPTIMIZATION_DELAY               | 10                                    |
    | NDB_DEFAULT_COLUMN_FORMAT            | FIXED                                 |
    | NDB_LOG_UPDATE_AS_WRITE              | ON                                    |
    | NDB_SHOW_FOREIGN_KEY_MOCK_TABLES     | OFF                                   |
    | NDB_VERSION_STRING                   | ndb-7.6.13                            |
    | NDBINFO_OFFLINE                      | OFF                                   |
    | NDB_INDEX_STAT_OPTION                | loop_enable=1000ms,loop_idle=1000ms,
    loop_busy=100ms,update_batch=1,read_batch=4,idle_batch=32,check_batch=8,
    check_delay=10m,delete_batch=8,clean_delay=1m,error_batch=4,error_delay=1m,
    evict_batch=8,evict_delay=1m,cache_limit=32M,cache_lowpct=90,zero_total=0      |
    | NDBINFO_MAX_ROWS                     | 10                                    |
    | NDB_BATCH_SIZE                       | 32768                                 |
    | NDB_USE_TRANSACTIONS                 | ON                                    |
    | NDB_NODEID                           | 0                                     |
    | NDB_ALLOW_COPYING_ALTER_TABLE        | ON                                    |
    | NDB_SLAVE_CONFLICT_ROLE              | NONE                                  |
    | NDB_REPORT_THRESH_BINLOG_MEM_USAGE   | 10                                    |
    | NDB_FULLY_REPLICATED                 | OFF                                   |
    | NDB_MGMD_HOST                        | 127.0.0.1                             |
    | NDB_REPORT_THRESH_BINLOG_EPOCH_SLIP  | 10                                    |
    | NDBINFO_MAX_BYTES                    | 0                                     |
    | NDB_LOG_BIN                          | ON                                    |
    | NDBINFO_TABLE_PREFIX                 | ndb$                                  |
    | NDB_LOG_EMPTY_EPOCHS                 | OFF                                   |
    | NDB_LOG_ORIG                         | OFF                                   |
    | NDB_LOG_EXCLUSIVE_READS              | OFF                                   |
    | NDB_LOG_TRANSACTION_ID               | OFF                                   |
    | NDB_DATA_NODE_NEIGHBOUR              | 0                                     |
    | NDB_CLEAR_APPLY_STATUS               | ON                                    |
    | NDBINFO_SHOW_HIDDEN                  | OFF                                   |
    | NDB_INDEX_STAT_ENABLE                | ON                                    |
    | NDB_DISTRIBUTION                     | KEYHASH                               |
    | NDB_BLOB_WRITE_BATCH_BYTES           | 65536                                 |
    | NDB_DEFERRED_CONSTRAINTS             | 0                                     |
    | NDB_TABLE_TEMPORARY                  | OFF                                   |
    | NDB_EXTRA_LOGGING                    | 1                                     |
    | NDB_AUTOINCREMENT_PREFETCH_SZ        | 1                                     |
    | NDB_FORCE_SEND                       | ON                                    |
    | NDB_OPTIMIZED_NODE_SELECTION         | 3                                     |
    | NDB_CLUSTER_CONNECTION_POOL          | 1                                     |
    | NDB_EVENTBUFFER_FREE_PERCENT         | 20                                    |
    | NDB_USE_COPYING_ALTER_TABLE          | OFF                                   |
    | NDB_CACHE_CHECK_TIME                 | 0                                     |
    | NDB_BLOB_READ_BATCH_BYTES            | 65536                                 |
    | NDB_LOG_EMPTY_UPDATE                 | OFF                                   |
    +--------------------------------------+---------------------------------------+
    61 rows in set, 1 warning (0.00 sec)
    mysql> SHOW WARNINGS;
    +---------+------+-------------------------------------------------------------+
    | Level   | Code | Message                                                     |
    +---------+------+-------------------------------------------------------------+
    | Warning | 1287 | 'INFORMATION_SCHEMA.GLOBAL_VARIABLES' is deprecated and will
    be removed in a future release. Please use performance_schema.global_variables
    instead                                                                        |
    +---------+------+-------------------------------------------------------------+

    Unlike the case with the SHOW VARIABLES statement, it is possible to select individual columns. For example:

    mysql> SELECT VARIABLE_VALUE 
        ->   FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES
        ->   WHERE VARIABLE_NAME = 'ndb_force_send';
    +----------------+
    | VARIABLE_VALUE |
    +----------------+
    | ON             |
    +----------------+

    See The INFORMATION_SCHEMA GLOBAL_VARIABLES and SESSION_VARIABLES Tables, and Server System Variables, for more information. See also Migrating to Performance Schema System and Status Variable Tables.

  • SELECT * FROM performance_schema.global_variables WHERE VARIABLE_NAME LIKE 'NDB%'

    This statement is the equivalent of the SHOW VARIABLES statement described in the previous item, and is preferred in NDB 7.5 and NDB 7.6 to querying the INFORMATION_SCHEMA.GLOBAL_VARIABLES table (now deprecated; see previous item). It provides output almost identical to that produced by SHOW VARIABLES, as shown here:

    mysql> SELECT * FROM performance_schema.global_variables
        ->   WHERE VARIABLE_NAME LIKE 'NDB%';
    +--------------------------------------+---------------------------------------+
    | VARIABLE_NAME                        | VARIABLE_VALUE                        |
    +--------------------------------------+---------------------------------------+
    | ndb_allow_copying_alter_table        | ON                                    |
    | ndb_autoincrement_prefetch_sz        | 1                                     |
    | ndb_batch_size                       | 32768                                 |
    | ndb_blob_read_batch_bytes            | 65536                                 |
    | ndb_blob_write_batch_bytes           | 65536                                 |
    | ndb_cache_check_time                 | 0                                     |
    | ndb_clear_apply_status               | ON                                    |
    | ndb_cluster_connection_pool          | 1                                     |
    | ndb_cluster_connection_pool_nodeids  |                                       |
    | ndb_connectstring                    | 127.0.0.1                             |
    | ndb_data_node_neighbour              | 0                                     |
    | ndb_default_column_format            | FIXED                                 |
    | ndb_deferred_constraints             | 0                                     |
    | ndb_distribution                     | KEYHASH                               |
    | ndb_eventbuffer_free_percent         | 20                                    |
    | ndb_eventbuffer_max_alloc            | 0                                     |
    | ndb_extra_logging                    | 1                                     |
    | ndb_force_send                       | ON                                    |
    | ndb_fully_replicated                 | OFF                                   |
    | ndb_index_stat_enable                | ON                                    |
    | ndb_index_stat_option                | loop_enable=1000ms,loop_idle=1000ms,
    loop_busy=100ms,update_batch=1,read_batch=4,idle_batch=32,check_batch=8,
    check_delay=10m,delete_batch=8,clean_delay=1m,error_batch=4,error_delay=1m,
    evict_batch=8,evict_delay=1m,cache_limit=32M,cache_lowpct=90,zero_total=0      |
    | ndb_join_pushdown                    | ON                                    |
    | ndb_log_apply_status                 | OFF                                   |
    | ndb_log_bin                          | ON                                    |
    | ndb_log_binlog_index                 | ON                                    |
    | ndb_log_empty_epochs                 | OFF                                   |
    | ndb_log_empty_update                 | OFF                                   |
    | ndb_log_exclusive_reads              | OFF                                   |
    | ndb_log_orig                         | OFF                                   |
    | ndb_log_transaction_id               | OFF                                   |
    | ndb_log_update_as_write              | ON                                    |
    | ndb_log_update_minimal               | OFF                                   |
    | ndb_log_updated_only                 | ON                                    |
    | ndb_mgmd_host                        | 127.0.0.1                             |
    | ndb_nodeid                           | 0                                     |
    | ndb_optimization_delay               | 10                                    |
    | ndb_optimized_node_selection         | 3                                     |
    | ndb_read_backup                      | OFF                                   |
    | ndb_recv_thread_activation_threshold | 8                                     |
    | ndb_recv_thread_cpu_mask             |                                       |
    | ndb_report_thresh_binlog_epoch_slip  | 10                                    |
    | ndb_report_thresh_binlog_mem_usage   | 10                                    |
    | ndb_row_checksum                     | 1                                     |
    | ndb_show_foreign_key_mock_tables     | OFF                                   |
    | ndb_slave_conflict_role              | NONE                                  |
    | ndb_table_no_logging                 | OFF                                   |
    | ndb_table_temporary                  | OFF                                   |
    | ndb_use_copying_alter_table          | OFF                                   |
    | ndb_use_exact_count                  | OFF                                   |
    | ndb_use_transactions                 | ON                                    |
    | ndb_version                          | 460301                                |
    | ndb_version_string                   | ndb-7.6.13                            |
    | ndb_wait_connected                   | 30                                    |
    | ndb_wait_setup                       | 30                                    |
    | ndbinfo_database                     | ndbinfo                               |
    | ndbinfo_max_bytes                    | 0                                     |
    | ndbinfo_max_rows                     | 10                                    |
    | ndbinfo_offline                      | OFF                                   |
    | ndbinfo_show_hidden                  | OFF                                   |
    | ndbinfo_table_prefix                 | ndb$                                  |
    | ndbinfo_version                      | 460301                                |
    +--------------------------------------+---------------------------------------+

    Unlike the case with the SHOW VARIABLES statement, it is possible to select individual columns. For example:

    mysql> SELECT VARIABLE_VALUE 
        ->   FROM performance_schema.global_variables
        ->   WHERE VARIABLE_NAME = 'ndb_force_send';
    +----------------+
    | VARIABLE_VALUE |
    +----------------+
    | ON             |
    +----------------+

    A more useful query is shown here:

    mysql> SELECT VARIABLE_NAME AS Name, VARIABLE_VALUE AS Value
         >   FROM performance_schema.global_variables
         >   WHERE VARIABLE_NAME
         >     IN ('version', 'ndb_version',
         >       'ndb_version_string', 'ndbinfo_version');
    +--------------------+-------------------+
    | Name               | Value             |
    +--------------------+-------------------+
    | ndb_version        | 460301            |
    | ndb_version_string | ndb-7.6.13        |
    | ndbinfo_version    | 460301            |
    | version            | 5.7.29-ndb-7.6.13 |
    +--------------------+-------------------+

    See Performance Schema System Variable Tables, and Server System Variables, for more information.

  • SHOW STATUS LIKE 'NDB%'

    This statement shows at a glance whether or not the MySQL server is acting as a cluster SQL node, and if so, it provides the MySQL server's cluster node ID, the host name and port for the cluster management server to which it is connected, and the number of data nodes in the cluster, as shown here:

    mysql> SHOW STATUS LIKE 'NDB%';
    +----------------------------------------------+-------------------------------+
    | Variable_name                                | Value                         |
    +----------------------------------------------+-------------------------------+
    | Ndb_api_wait_exec_complete_count             | 2                             |
    | Ndb_api_wait_scan_result_count               | 5                             |
    | Ndb_api_wait_meta_request_count              | 54                            |
    | Ndb_api_wait_nanos_count                     | 1849442202547                 |
    | Ndb_api_bytes_sent_count                     | 2044                          |
    | Ndb_api_bytes_received_count                 | 81384                         |
    | Ndb_api_trans_start_count                    | 2                             |
    | Ndb_api_trans_commit_count                   | 1                             |
    | Ndb_api_trans_abort_count                    | 0                             |
    | Ndb_api_trans_close_count                    | 2                             |
    | Ndb_api_pk_op_count                          | 1                             |
    | Ndb_api_uk_op_count                          | 0                             |
    | Ndb_api_table_scan_count                     | 1                             |
    | Ndb_api_range_scan_count                     | 0                             |
    | Ndb_api_pruned_scan_count                    | 0                             |
    | Ndb_api_scan_batch_count                     | 2                             |
    | Ndb_api_read_row_count                       | 4                             |
    | Ndb_api_trans_local_read_row_count           | 2                             |
    | Ndb_api_adaptive_send_forced_count           | 0                             |
    | Ndb_api_adaptive_send_unforced_count         | 3                             |
    | Ndb_api_adaptive_send_deferred_count         | 0                             |
    | Ndb_api_event_data_count                     | 0                             |
    | Ndb_api_event_nondata_count                  | 0                             |
    | Ndb_api_event_bytes_count                    | 0                             |
    | Ndb_api_wait_exec_complete_count_slave       | 0                             |
    | Ndb_api_wait_scan_result_count_slave         | 0                             |
    | Ndb_api_wait_meta_request_count_slave        | 0                             |
    | Ndb_api_wait_nanos_count_slave               | 0                             |
    | Ndb_api_bytes_sent_count_slave               | 0                             |
    | Ndb_api_bytes_received_count_slave           | 0                             |
    | Ndb_api_trans_start_count_slave              | 0                             |
    | Ndb_api_trans_commit_count_slave             | 0                             |
    | Ndb_api_trans_abort_count_slave              | 0                             |
    | Ndb_api_trans_close_count_slave              | 0                             |
    | Ndb_api_pk_op_count_slave                    | 0                             |
    | Ndb_api_uk_op_count_slave                    | 0                             |
    | Ndb_api_table_scan_count_slave               | 0                             |
    | Ndb_api_range_scan_count_slave               | 0                             |
    | Ndb_api_pruned_scan_count_slave              | 0                             |
    | Ndb_api_scan_batch_count_slave               | 0                             |
    | Ndb_api_read_row_count_slave                 | 0                             |
    | Ndb_api_trans_local_read_row_count_slave     | 0                             |
    | Ndb_api_adaptive_send_forced_count_slave     | 0                             |
    | Ndb_api_adaptive_send_unforced_count_slave   | 0                             |
    | Ndb_api_adaptive_send_deferred_count_slave   | 0                             |
    | Ndb_slave_max_replicated_epoch               | 0                             |
    | Ndb_api_event_data_count_injector            | 0                             |
    | Ndb_api_event_nondata_count_injector         | 0                             |
    | Ndb_api_event_bytes_count_injector           | 0                             |
    | Ndb_cluster_node_id                          | 100                           |
    | Ndb_config_from_host                         | 127.0.0.1                     |
    | Ndb_config_from_port                         | 1186                          |
    | Ndb_number_of_data_nodes                     | 2                             |
    | Ndb_number_of_ready_data_nodes               | 2                             |
    | Ndb_connect_count                            | 0                             |
    | Ndb_execute_count                            | 0                             |
    | Ndb_scan_count                               | 0                             |
    | Ndb_pruned_scan_count                        | 0                             |
    | Ndb_schema_locks_count                       | 0                             |
    | Ndb_api_wait_exec_complete_count_session     | 0                             |
    | Ndb_api_wait_scan_result_count_session       | 0                             |
    | Ndb_api_wait_meta_request_count_session      | 0                             |
    | Ndb_api_wait_nanos_count_session             | 0                             |
    | Ndb_api_bytes_sent_count_session             | 0                             |
    | Ndb_api_bytes_received_count_session         | 0                             |
    | Ndb_api_trans_start_count_session            | 0                             |
    | Ndb_api_trans_commit_count_session           | 0                             |
    | Ndb_api_trans_abort_count_session            | 0                             |
    | Ndb_api_trans_close_count_session            | 0                             |
    | Ndb_api_pk_op_count_session                  | 0                             |
    | Ndb_api_uk_op_count_session                  | 0                             |
    | Ndb_api_table_scan_count_session             | 0                             |
    | Ndb_api_range_scan_count_session             | 0                             |
    | Ndb_api_pruned_scan_count_session            | 0                             |
    | Ndb_api_scan_batch_count_session             | 0                             |
    | Ndb_api_read_row_count_session               | 0                             |
    | Ndb_api_trans_local_read_row_count_session   | 0                             |
    | Ndb_api_adaptive_send_forced_count_session   | 0                             |
    | Ndb_api_adaptive_send_unforced_count_session | 0                             |
    | Ndb_api_adaptive_send_deferred_count_session | 0                             |
    | Ndb_sorted_scan_count                        | 0                             |
    | Ndb_pushed_queries_defined                   | 0                             |
    | Ndb_pushed_queries_dropped                   | 0                             |
    | Ndb_pushed_queries_executed                  | 0                             |
    | Ndb_pushed_reads                             | 0                             |
    | Ndb_last_commit_epoch_server                 | 29347511533580                |
    | Ndb_last_commit_epoch_session                | 0                             |
    | Ndb_system_name                              | MC_20191209172820             |
    | Ndb_conflict_fn_max                          | 0                             |
    | Ndb_conflict_fn_old                          | 0                             |
    | Ndb_conflict_fn_max_del_win                  | 0                             |
    | Ndb_conflict_fn_epoch                        | 0                             |
    | Ndb_conflict_fn_epoch_trans                  | 0                             |
    | Ndb_conflict_fn_epoch2                       | 0                             |
    | Ndb_conflict_fn_epoch2_trans                 | 0                             |
    | Ndb_conflict_trans_row_conflict_count        | 0                             |
    | Ndb_conflict_trans_row_reject_count          | 0                             |
    | Ndb_conflict_trans_reject_count              | 0                             |
    | Ndb_conflict_trans_detect_iter_count         | 0                             |
    | Ndb_conflict_trans_conflict_commit_count     | 0                             |
    | Ndb_conflict_epoch_delete_delete_count       | 0                             |
    | Ndb_conflict_reflected_op_prepare_count      | 0                             |
    | Ndb_conflict_reflected_op_discard_count      | 0                             |
    | Ndb_conflict_refresh_op_count                | 0                             |
    | Ndb_conflict_last_conflict_epoch             | 0                             |
    | Ndb_conflict_last_stable_epoch               | 0                             |
    | Ndb_index_stat_status                        | allow:1,enable:1,busy:0,
    loop:1000,list:(new:0,update:0,read:0,idle:0,check:0,delete:0,error:0,total:0),
    analyze:(queue:0,wait:0),stats:(nostats:0,wait:0),total:(analyze:(all:0,error:0),
    query:(all:0,nostats:0,error:0),event:(act:0,skip:0,miss:0),
    cache:(refresh:0,clean:0,pinned:0,drop:0,evict:0)),
    cache:(query:0,clean:0,drop:0,evict:0,usedpct:0.00,highpct:0.00)               |
    | Ndb_index_stat_cache_query                   | 0                             |
    | Ndb_index_stat_cache_clean                   | 0                             |
    +----------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

    If the MySQL server was built with clustering support, but it is not connected to a cluster, all rows in the output of this statement contain a zero or an empty string.

    See also SHOW STATUS Statement.

  • SELECT * FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME LIKE 'NDB%';

    This statement, although deprecated in NDB 7.5 and NDB 7.6, can be be used if show_compatibility_56 is enabled to obtain similar output to the SHOW STATUS statement discussed in the previous item; the preferred method is to query the performance_schema.global_status table (see next item). Unlike the case with SHOW STATUS, it is possible using the SELECT to extract values in SQL for use in scripts for monitoring and automation purposes.

    See The INFORMATION_SCHEMA GLOBAL_STATUS and SESSION_STATUS Tables, as well as Migrating to Performance Schema System and Status Variable Tables, for more information.

  • SELECT * FROM performance_schema.global_status WHERE VARIABLE_NAME LIKE 'NDB%'

    This statement provides similar output to the SHOW STATUS statement discussed previously. Unlike the case with SHOW STATUS, it is possible using SELECT statements to extract values in SQL for use in scripts for monitoring and automation purposes.

    See Performance Schema Status Variable Tables, for more information.

  • SELECT * FROM INFORMATION_SCHEMA.PLUGINS WHERE PLUGIN_NAME LIKE 'NDB%'

    This statement displays information from the INFORMATION_SCHEMA.PLUGINS table about plugins associated with NDB Cluster, such as version, author, and license, as shown here:

    mysql> SELECT * FROM INFORMATION_SCHEMA.PLUGINS
         >     WHERE PLUGIN_NAME LIKE 'NDB%'\G
    *************************** 1. row ***************************
               PLUGIN_NAME: ndbcluster
            PLUGIN_VERSION: 1.0
             PLUGIN_STATUS: ACTIVE
               PLUGIN_TYPE: STORAGE ENGINE
       PLUGIN_TYPE_VERSION: 50729.0
            PLUGIN_LIBRARY: NULL
    PLUGIN_LIBRARY_VERSION: NULL
             PLUGIN_AUTHOR: MySQL AB
        PLUGIN_DESCRIPTION: Clustered, fault-tolerant tables
            PLUGIN_LICENSE: GPL
               LOAD_OPTION: ON
    *************************** 2. row ***************************
               PLUGIN_NAME: ndbinfo
            PLUGIN_VERSION: 0.1
             PLUGIN_STATUS: ACTIVE
               PLUGIN_TYPE: STORAGE ENGINE
       PLUGIN_TYPE_VERSION: 50729.0
            PLUGIN_LIBRARY: NULL
    PLUGIN_LIBRARY_VERSION: NULL
             PLUGIN_AUTHOR: Sun Microsystems Inc.
        PLUGIN_DESCRIPTION: MySQL Cluster system information storage engine
            PLUGIN_LICENSE: GPL
               LOAD_OPTION: ON
    *************************** 3. row ***************************
               PLUGIN_NAME: ndb_transid_mysql_connection_map
            PLUGIN_VERSION: 0.1
             PLUGIN_STATUS: ACTIVE
               PLUGIN_TYPE: INFORMATION SCHEMA
       PLUGIN_TYPE_VERSION: 50729.0
            PLUGIN_LIBRARY: NULL
    PLUGIN_LIBRARY_VERSION: NULL
             PLUGIN_AUTHOR: Oracle Corporation
        PLUGIN_DESCRIPTION: Map between mysql connection id and ndb transaction id
            PLUGIN_LICENSE: GPL
               LOAD_OPTION: ON

    You can also use the SHOW PLUGINS statement to display this information, but the output from that statement cannot easily be filtered. See also The MySQL Plugin API, which describes where and how the information in the PLUGINS table is obtained.

You can also query the tables in the ndbinfo information database for real-time data about many NDB Cluster operations. See Section 7.10, “ndbinfo: The NDB Cluster Information Database”.