Re: kdb equivalent of pandas groupby

[Laura]

For this query you are better using the ‘update’ query rather than ‘select’.

 

This will show you the updated trade table but it will not save it in place as the new trade table. If you want to save the new column to the trade table permanently then use `trades in the update statement, i.e. update change:price-prev price by sym from `trade

Here’s a link if you want to read more about the update statement.

https://code.kx.com/q4m3/9_Queries_q-sql/#95-the-update-template