Assertion: column's value | /r/HasProperty | null
Facets:
Source sentences:
text: If the added column allows null values and WITH VALUES is specified, the default value is stored in the new column that is added to existing rows.
text: For MyISAM tables, NULL columns require additional space in the row to record whether their values are NULL .
text: Sparse columns that contain null values are omitted from the XML representation for the column set.