column "{id}" is an impure computed column and is not materialised into the store

Warnings reference › ingest.impure.*

Identifier

ingest.impure.*

Raised by

The grid (core)

Since

1.0.1

What happened

An impure computation is not a function of the stored data, so there is nothing stable to materialise: the column layer re-evaluates it on every read instead. The column works; it does not get the store's speed, and under dropSourceRows it cannot be served at all.

The fix

Nothing, if the impurity is deliberate. Make the column pure - feed the varying input in as data - to have it stored.

Reference

Covered in full at the API reference.