How to run the functional version of <select from 10#trade>?

Question

I want to execute the following in an RDB or any other proc:

?[(10;#;`trade);();0b;()] (1)

I have a parser that converts string qsql queries to functional form and then send them from the gw to the correct process to be resolved. All well with more complex queries , but now someone wants to run 10#trade.

In order for my parser to work I need to convert it to the functional form of select from 10#trade. The only problem is that when I do that I get a Mismatched error on the process.

I cannot seem to run (1) even directly on the process.

Answer 1

Your example is trying to mix a parse tree with a functional select which is not going to work.

You can limit from within a select/functional-select:

• https://code.kx.com/q/basics/funsql/#rank-5

parse"select[5] from trade"
?
`trade
()
0b
()
5
?[`trade;();0b;();5]
a
-
1
1
1
1
1

• https://code.kx.com/q/basics/parsetrees/
• https://code.kx.com/q/wp/parse-trees/
• https://code.kx.com/q/basics/funsql/

To do exactly what you asked would be:

?[eval  (#;5;`trade);();0b;()]
a
-
1
1
1
1
1