Hi, Chen,

Presumably you are talking about the time spent by FastBit program
ibis.  The short answer is that we would need more specific
information in order to know why a query takes longer to answer than
another.  If one needs to read anything from disk, my expectation is
that it would take at least 10ms if the operation actual touches disk.
 It could take longer if it has to access multiple files.  Anyway, I
can not tell you more without knowing more information.

Thanks.

John


On 6/24/15 12:35 AM, hangchen wrote:
> Hi Kevin:
> 
> There is one issue we observed is we have a table with rows=[78098901]
> columns=[114], we query this table in this way:"column1,column2 where
> id=123422". id is one of the columns which has very high cardinality
> should same with rows. The response time depends on certain id number,
> for example:
> 
> duration| id
> 
> 200ms 128959558
> 
> 200ms 102510976
> 
> 200ms 106972647
> 
> 
> 20ms  15624187
> 
> 20ms  659153162243
> 
> 
> 2ms   727671377921
> 
> 2ms   8255237
> 
> 
> My question is, do you think this response time is reasonable in this
> size of table, any optimization option we could take?
> 
> 
> 
> Chen HANG
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