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Number of seconds to wait before detecting a timeout during schema distribution. This can indicate that other SQL nodes are experiencing excessive activity, or that they are somehow being prevented from acquiring necessary resources at this time. 

• ndb_schema_dist_upgrade_allowed 

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Allow upgrading of the schema distribution table when connecting to NDB . When true (the default), this change is deferred until all SQL nodes have been upgraded to the same version of the NDB Cluster software. 

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• ndb_show_foreign_key_mock_tables 

## Note 

The performance of the schema distribution may be somewhat degraded until the upgrade has been performed. 

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