问题
Consider the table:
q)trade
stock price amt time
-----------------------------
ibm 121.3 1000 09:03:06.000
bac 5.76 500 09:03:23.000
usb 8.19 800 09:04:01.000
and the list:
q)x: 10000 20000
The following query:
q)select from trade where price < x[first where (x - price) > 100f]
'length
fails as above. How can I pass the current row value of price in each iteration of the search query?
While price[0] in the square brackets above works, that's obviously not what I want. I even tried price[i] but that gives the same error.
来源：https://stackoverflow.com/questions/33386027/iterate-over-current-row-values-in-kdb-query