Hi,
I have a question on Hive Optimizer. I have a table with partition columns
eg.,Sales partitioned by year, month, day. Assume that I have two years
worth of data on this table. I'm running two queries on this table.
Query 1: Select * from Sales where year=2015 and month = 5 and day between
1 and 7
Query 2: Select * from Sales where concat_ws('-',cast(year as
string),lpad(cast(month as string),2,'0'),lpad(cast(day as string),2,'0'))
between '2015-01-01' and '2015-01-07'
When I ran Explain command on the above two queries I get a Filter
operation for the 2nd Query and there is no Filter Operation for the first
query.
My question is: Do both queries use the partitions or is it used only in
Query 1 and for Query 2 it will be a scan of all the data?
Thanks for your help.
Thanks,
Appan
