q)t:( sym:9?ab; qty:9?9;
exchange:9#NYSENASDAQBATSCMELSE)<br> q)t<br> sym qty exchange<br> ----------------<br> a 7 NYSE<br> a 6 NASDAQ<br> a 3 BATS<br> b 4 CME<br> a 3 LSE<br> a 4 NYSE<br> b 8 NASDAQ<br> a 4 BATS<br> b 6 CME<br> <br> </tt><tt>/ our selected list</tt> <tt>q)l:NYSENASDAQBATS
/ select only those in our list l
q)select count i , sum qty by exchange from t where exchange in
l
exchange| x qty
--------| -----
BATS | 2 7
NASDAQ | 2 14
NYSE | 2 11
/ select grouping by our list l
q)select count i , sum qty by exchange in l from t
l| x qty
-| -----
0| 3 13
1| 6 32
q)
/ custom groupings using dictionary
q)d:(NYSENASDAQBATSLSE!AABB)
q)d
NYSE | A
NASDAQ| A
BATS | B
LSE | B
q)select count i , sum qty by `other^d[exchange] from t
exchange| x qty
--------| -----
A | 4 25
B | 3 10
other | 2 10
Regards,
Ryan Hamilton
On 4/10/2013 9:01 PM, CHEN, Cheng wrote:
Hi,
quite often we use the following syntax:
select count i , sum qty by exchange from mytable
can I force the exchange to be a list that I predefined? something like :
select count i , sum qty by NYSENASDAQ`BATS from mytable