NULL Keyword
This example demonstrates how to use the NULL keyword in template filters.
The NULL keyword allows you to filter records where a field value is NULL (missing) or NOT NULL.
- **= NULL**: Matches records where the field is null (DBNull.Value or native null).
- **<> NULL**: Matches records where the field is not null.
- The NULL keyword is case-insensitive (NULL, null, Null are all valid).
- Empty string "" is NOT considered NULL.
- NULL can be combined with other conditions using AND / OR / NOT.