a spread join wrote the field "{fieldName}" ...

Warnings reference › router:spread-duplicate

Identifier

router:spread-duplicate

Raised by

Data Router

Since

1.84.0

What happened

Two attribute rows resolved to the SAME spread field name for one parent. The router is last-writer-wins in the attribute source's order - the later row's value stands, the earlier is overwritten - rather than collecting or throwing. Warned once per field name.

The fix

De-duplicate the attribute rows upstream, or make name/prefix produce distinct field names per attribute.

The smallest fix

join: { from: 'companyAttr', foreignKey: 'companyId', spread: { name: 'attribute', value: 'value', prefix: 'cf_' } }

Reference

Covered in full at the API reference.