Nullability Model

Nullability in POCO DataSet is determined entirely by ColumnMetadata, not by runtime conventions or hidden rules. This explicit model ensures predictable behavior across serialization, UI rendering, and validation.

Core Rules

• If a column is marked nullable, DataRow may store null for that column.
• If a column is non-nullable, DataRow must store a valid value.
• UI components use this information for validation and control rendering.
• Serialization preserves nulls exactly as declared.

This model ensures consistency across server, database, and client layers.

Table of Content POCO DataSet Overview of Data Model