CASSANDRA-13001 Implement appender of slow queries to system_views.slow_queries table

[smiklosovic]

patch by Stefan Miklosovic; reviewed by TBD for CASSANDRA-13001

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The Cassandra Jira

[bbotella]

Is it worth adding a debug logger message stating that the table has been truncated?

[smiklosovic]

I dont think so, really.

[bbotella]

Should we add a logger debug if message is not added to the buffer due to buffer size?

[smiklosovic]

That would most probably cause a flood of debug messages every time we are "over the limit" unless the logger is no-spamming one. I would keep it like it is.

[bbotella]

Can we use assertEmpty?

[smiklosovic]

I don't see any simple way to do that because executeNet returns ResultSet from driver but assertEmpty accepts UntypedResultSet