While doing some routine fiddling regarding some topic I've now
forgotten, I discovered that ndb_restore
was doing
something quite surprising. It's been common wisdom for some time
that one can use ndb_restore -m
to restore metadata
into a new cluster and automatically have your data
re-partitioned across the data nodes in the destination cluster.
In fact, this was the recommended procedure for adding nodes to a
cluster before online add node came along. Since MySQL Cluster
7.0, though, ndb_restore
hasn't behaved that way,
though that change in behavior doesn't seem to be documented and
most don't know that the change ever took place.
I'll go through some of the methods you can use to find
information about the partitioning strategy for an NDB table,
talk a bit about why ndb_restore
stopped working the
way most everyone expected (and still expect) it to, and discuss
some possible …
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