kdb: Is there a way to efficiently merge two sorted tables?

Question

Say we have two tables both sorted on the time column:

t1:`time xasc ([]time:5?100;v:5?1000)
t2:`time xasc ([]time:5?100;v:5?1000)

Is there an efficient way to get the same result as `time xasc t1,t2 , using the fact that the two tables are already sorted? I looked at aj but I wasn't able to find the "combine two tables" functionality I need here.

Answer 1

There is no native merge-sort/binary-sort in kdb so the optimal available approach is asc x,y. If you go down the path of replicating a merge/binary sort in kdb then you're unlikely to get it faster than the native asc x,y. You could alternatively try to write a merge/binary sort in C and import a shared library to use in kdb