Functional upsert

Community Support
1

I’m having some trouble translating an upset into functional form:

q)ticks:([sym:()] price:(); size:(); ae:())

q)parse “ticks upsert (AAPL;100.0;10;1b)”

.[;();,;]

,`ticks

(enlist;,`AAPL;100f;10;1b)


understand line #2 and #3 are first and second argument, respectively. How would these arguments be applied to the dot (amend)? Guess I don’t understand the amend function correctly.


Thanks.

2

Here you go:

q).[ticks;();,;(`AAPL;100f;10;1b)]

sym  price size ae

AAPL 100   10   1

3

Thank you Himanshu.

Guess I was confused over the 3rd argument (,) - is it interpreted as join? I was replacing it with enlist.

4

You’re welcome!

@ and . and not like functional forms of select/update (? and !) where the parameters are t,c,b,a. 
@ and . have different parameters. 

You can read about them here:

http://code.kx.com/wiki/JB:QforMortals2/functions#Functional\_Forms\_of\_Amend

Basically, 

first parameter (`ticks) is the table/list/dictionary, 

second parameter () is a subset of that data set that you want to modify, 

third parameter (,) is the function/operation you want to apply to that subset and 

fourth parameter (`AAPL;100f;10;1b) is any argument for the function/operation passed as the third argument.