KDB: try-catch over a list and return list of fails - error-handling

Question

I want to run the function
{`Security$x}
over a list
order`KDB_SEC_ID
and return the list of values that failed. I have the below, which works, but I'm wondering if there is a neater way to write this without the use of a do loop.
Example Code:
idx:0;
fails:();
do[count (order`KDB_SEC_ID);
error:#[{`Security$x};(order`KDB_SEC_ID)[idx];0Nj];
if[error=0Nj;fails:fails,(order`KDB_SEC_ID)[idx]];
idx:idx+1;
];
missingData:select from order where KDB_SEC_ID in distinct fails;

Answer 1

I agree that Terry's answer is the simplest method but here is a simpler way to do the method you were trying to help you see how achieve it without using do loops
q)SECURITY
`AAPL`GOOG`MSFT
q)order
KDB_SEC_ID val
--------------
AAPL 1
GOOG 2
AAPL 3
MSFT 4
IBM 5
q)order where #[{`SECURITY$x;0b};;1b] each order`KDB_SEC_ID
KDB_SEC_ID val
--------------
IBM 5
It outputs a 0b if it passes and 1b if it fails resulting in a boolean list. Using where on a boolean list returns the indices where the 1b's occur which you can use to index into order to return the failing rows.

Answer 2

If your test is to check which of the KDB_SEC_ID's can be enumerated against the Security list, couldn't you do
q)select from order where not KDB_SEC_ID in Security
Or am I missing something?
To answer your question in a more general case, you could achieve a try-catch over a list to return the list of fails using something like
q){x where #[{upper x;0b};;1b] each x}(2;`ab;"Er";1)
2 1