NullDefinition.php
Classes
- NullDefinition
- The bottom of the type lattice: the column's type is not known. Absorbed by merge() in both directions - null ⊔ T = ?T, T ⊔ null = ?T, null ⊔ null = null. Reaches a materialized Schema only when a column is null in every observed row and no type was declared; that is Parquet's UNKNOWN and Iceberg's unknown. A column that holds strings and sometimes null is StringDefinition(nullable: true), never this.