The format of a generated XML schema for nullstyle=omit specifies the minOccurs="0" and maxOccurs="1" attribute in each nullable columns declaration. For example:
select forxmlschemaj("select 1,null", "nullstyle=omit")
-----------------------
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:sqlxml="http://www.iso-standards.org/mra/9075/sqlx">
<xsd:import namespace="http://www.w3.org/2001/XMLSchema"
schemaLocation="http://www.iso-standards.org/mra/9075/sqlx.xsd" />
<xsd:complexType name="RowType.resultset">
<xsd:sequence>
<xsd:element name="C1" type="INTEGER" />
<xsd:element name="C2" type="INTEGER"
minOccurs="0" maxOccurs="1"/>
</xsd:sequence>
</xsd:complexType>
<xsd:complexType name="TableType.resultset">
<xsd:sequence>
<xsd:element name="row" type="RowType.resultset"
minOccurs="0" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
<xsd:simpleType name="INTEGER">
<xsd:restriction base="xsd:integer">
<xsd:maxInclusive value="2147483647"/>
<xsd:minInclusive value="-2147483648"/>
</xsd:restriction>
</xsd:simpleType>
<xsd:element name="resultset" type="TableType.resultset"/>
</xsd:schema>
