KX Fundamentals Capstone

[WilliamO1]

Hey, I am having an issue with the Fundamentals Capstone course (on Developer) with trying to obtain the unique option IDs from the trade table in part 1. I have loaded the trade table from the partitioned database using the table importer. 

I am using the following code but I am getting a par error - unable to operate on a partitioned table.

q code: uniqueOpts:distinct trade`option_id

Does anyone have any thoughts on how to answer this?

Thanks 🙂

[LeahS]

Hello,

Thanks for sharing this with the community. Great content!

I believe the error generated is a result of your method for retrieving the unique OptionIDs. Given your table is partitioned, this method of taking columns from tables will not work . Hence the 'unable to operate on a partitioned table' error.

I suggest querying the table, meaning avail of Functional qSQL Statements as an alternate approach to obtain the unique OptionIDs from the trade table.

Functional qSQL information can be studied here: https://code.kx.com/q/basics/funsql/ 

Specifically focus your attention on the functional form 'exec'  https://code.kx.com/q/ref/exec/ 

In summary, rather than 

uniqueOpts:distinct trade`option_id

Create uniqueOpts by following the syntax below (provided in the previous link) where square brackets mark optional elements. This is what we refer to as 'querying' the table. 

Spoiler

exec [distinct] ps [by pb] from texp [where pw]

The above code is a 'hint' and requires modification.

Hope this helps. 

Kind regards,

Leah 

[matt_moore · Accepted solution]

exec won't work on a partitioned table directly. Need to have a select statement first.

Spoiler

exec option_id from select distinct option_id from trade

I would also recommend starting with qSQL  before moving on to functional qSQL.

QSQL query templates | Basics | kdb+ and q documentation - Kdb+ and q documentation (kx.com)

[WilliamO1]

Thank you for the help, Matt and Leah! 🙂