hi, i saw through help.q that one of the attributes signifies that atable is grouped. What are the reasons for using a grouped table? I’mguessing it is used to compress tables because if a table hasduplicates then just specifying their indices instead of actual rowsmight take off some overhead. Thanks!
not quite
the group attribute `g# is applied to a column, not to a table
if you have a column you want to search with values:
7 7 7 8 8 8 1 1 1 2 2 2
it’s most efficient to store that with a partition attribute `p# which will mark unique values and start points
but you can’t do that when there’s a repeated value elsewhere as with:
7 7 7 8 8 8 1 1 1 2 2 2 7
then you use a `g# attribute which keeps unique values and found locations
these are both to speed searching, not to aid compression
see:
https://code.kx.com/trac/wiki/QforMortals2/tables#Attributes